A memorial for two police officers who were shot and...

A memorial for two police officers who were shot and killed on Saturday, Dec. 20, 2014, lies outside the 84th Precinct in Brooklyn on Sunday, Dec. 21. Officers Wenjian Liu, 32, and Rafael Ramos, 40, were ambushed by Ismaaiyl Brinsley, 28, as they sat in their cruiser in the Bedford-Stuyvesant area of Brooklyn, police say. Credit: Steven Sunshine

The man who gunned down two NYPD officers in their patrol car Saturday has a long criminal record in Georgia and Ohio and expressed his anger at police and government in "rants" on social media, NYPD Chief of Detectives Robert Boyce said Sunday.

Ismaaiyl Brinsley traveled to New York on Saturday after wounding his ex-girlfriend. He shot four times at the two officers -- Wenjian Liu, 32, and Rafael Ramos, 40 -- at point-blank range as they sat in their patrol car near Myrtle and Tompkins avenues in Brooklyn's Bedford-Stuyvesant section at 2:47 p.m., he said. Police have recovered the bullets in addition to those from the Baltimore scene, Boyce said.

Just before the killings, Brinsley, 28, told two male witnesses "Watch what I am going to do," Boyce said, adding that the shooter told them to follow him on Instagram. He then walked past the officers, circled around and came up behind them, Boyce said, adding that they probably never saw him coming.

The shooter may have had an undiagnosed mental illness, according to his family, and may have been on medication "later on in life," Boyce said in a briefing in Manhattan. But he said he had no official reports of any mental illness.

"He had a troubled childhood that was often violent," said Boyce, adding that Brinsley, who was born in Brooklyn and is estranged from family there, tried to hang himself a year ago.

Boyce had 15 prior arrests in Georgia and Ohio for assorted crimes and had done a two-year prison sentence in Georgia from August 2011 to July 2013 in addition to stints in local jails in Georgia.

Boyce said police had been able to track most of Brinsley's movements through surveillance video and eyewitness starting in Baltimore and up until about two hours before the shootings and his suicide on a New York City subway platform.

In particular, Boyce highlighted the role of two Con Edison workers who witnessed the shooting and chased after Brinsley until police officers caught up with him on the subway platform.

"We can't thank those two individuals enough," Boyce said.

Boyce said Brinsley had no gang affiliation or tattoos. His family is Muslim but the NYPD found no indication that he was religious or that the slaying was motivated by religion. He said the family said he never manifested "any radicalization."

In social media, Brinsley expressed anger against police, the government and himself, Boyce said. Most of the rants were on Instagram, he said.

But Boyce said the investigation is still ongoing as to his exact motivations or whether he was a participant in protests against deaths in police custody in New York.

"We are still peeling this thing back," Boyce said.

Shortly afterward, in a news conference, Lucy Ramos, a member of Ramos' family said, "I would like to thank all those who have expressed their sympathy and support for our beloved family member Rafael Ramos who will always be loved and missed by many." She asked the community to "move forward and find an amicable path to a peaceful coexistence," and added, "we would like to extend our condolences to the Liu family as well."

Other community leaders and family friends spoke as well, many criticizing Mayor Bill de Blasio for what they viewed as his lack of support for the NYPD.

"We are praying today that dignity might prevail," said Bishop David Benke. Saying "we are fractured among ourselves," Benke prayed for the family, the city and for "honest conversation."

"Protect those officers out in the streets Heavenly Father," he added.

Sunday, there was a makeshift memorial at the shooting scene in Brooklyn, with flowers, candles and cards, where a steady stream of people were coming by to pay their respects. Later Sunday, there was a candlelight vigil there, where the diverse crowd stood in the street and sung hymns.

Gov. Andrew M. Cuomo had visited the Ramos family at their home.

Afterward, Cuomo said, "I spoke to Mrs. Liu and Mrs. Ramos and the boys and they're shocked, they're stunned as one would expect so it's just a personal tragedy that happened this time of year -- it's just crushing. You can see that Mr. Ramos was very much a family man and was very close to his boys and what they were accomplishing, so it's a personal tragedy. It's also a tragedy for the City of New York and for the state of New York."

Sunday, the NYPD issued a directive stating that all NYPD foot patrol officers will work in pairs "until further notice."

The directive to patrol and desk officers said, "Effective immediately and until further notice, all foot posts are to be assigned in pairs. There are to be no solo foot posts citywide. All uniform members of service shall arrive and remain on post together. Meal and personal breaks will also be taken in pairs."

Officers on patrol "should maintain a heightened level of awareness," according to the directive, which continued, "Please remind all uniform members of the service to remain vigilant on post, and to approach all situations tactically."

Earlier on Sunday, NYPD Commissioner William Bratton put out a message via tweet to the rank and file, saying "Put the flags at half-mast. Today, two of our officers were shot and killed, with no warning, no provocation, in the 079 Precinct. They were assassinated -- targeted for their uniform, and for the responsibility they embraced: to keep the people of this city safe."

"Police Officer Wenjian Liu and Police Officer Rafael Ramos will be remembered. They will join a line that is too long, a line of partners who served together and made the ultimate sacrifice together. . . . We will not forget them, and we will not forget the oath they took -- that we all took, too -- but for which they died."

He closed by saying, "And to all members of the service, be safe."

The Suffolk and Nassau police departments said they were taking precautions following the killings. All Suffolk police officers were instructed "to maintain a heightened level of awareness," though there are no specific credible threats, police said in a statement.

Nassau police said the department is "taking appropriate precautions," a spokesman said.

Police in Newark have also been told not to patrol alone and the state police union also urged extra caution.

The fatal shootings came after weeks of protests in city streets protesting the lack of a grand jury indictment in the deaths of two unarmed black men, Eric Garner and Michael Brown, at the hands of police. NYPD union officials have also criticized de Blasio, saying he has the "blood" of the officers on his hands.

President Barack Obama phoned Bratton to express condolences for the killings and to offer support in the coming days and weeks. Obama reiterated his call for the American people to reject violence and words that harm, and turn to words that heal -- prayer, patient dialogue, and sympathy for the friends and family of the fallen.

Cardinal Timothy Dolan, in a Sunday Mass, told police and city officials in attendance that the Church is praying for the police department, as he called for unity and healing in a city "tempted by tension and division."

"We are in solidarity with you," Dolan said in his sermon at St. Patrick's Cathedral, in a Mass attended by de Blasio, Bratton, Chief of Department James P. O'Neill, and first lady Chirlane McCray.

At the Ramos family's church, Christ Tabernacle in Brooklyn, senior pastor Michael Durso said during his sermon at the 1 p.m. worship service that he was at the hospital Saturday night in support of Ramos.

"We gotta do everything to help them," he said of the Ramos family. "A sea of police officers were standing in that room. They were in full force."

The pastor said one woman, a chaplain at the hospital, reminded him to give praise at all times before she started singing "Amazing Grace."

"It was amazing . . . it was still pain in the room and grief in the room, but that song just helped us go to the next step," Durso said in front of hundreds of people.

Earlier Sunday, Rep. Peter King (R-Seaford) said de Blasio and Obama helped create a climate that, in part, led to the shootings of the two NYPD officers in Brooklyn.

"There's definitely a responsibility on the part of Mayor de Blasio and President Obama, as far as the rhetoric and tone and climate. They bear responsibility," King said Sunday morning in an interview with Newsday.

At St. Patrick's on Sunday, Dolan said, "Our beloved city needs light and wisdom that only the Lord can give. As we console the sobbing families, we pray for our brothers and sisters in uniform that God may guide us."

"We tear up thinking of the heartbroken families and the police department is mourning a death in their own family as we worry about a city tempted by tension and division," Dolan said. "The more we are tested, the stronger we get. Now more than ever, we need a little Christmas right this very minute."

Dolan, invoking a biblical passage in which God speaks to the Virgin Mary, told the police department: "Be not afraid. We are with you." He told Bratton to tell his rank and file that there was a "thundering prayer" from the church for officers.

Dolan said he first learned of the shooting about 4:15 p.m. Saturday while he was about to deliver Mass in the Bronx. Dolan saw the distraught police officers assigned to the church and asked them to take him across the street to the 46th Precinct, where officers prayed on their knees with their hats on the floor, he said.

Outside the cathedral, NYPD officers consoled each other and wiped away tears, resting their heads against the cathedral walls. Officers wore black bands over their badges in honor of their two fallen colleagues.

Cuomo released a statement saying, "This deplorable act of violence is the opposite of what New York is and what New Yorkers believe in. These brave officers, along with the over 34,000 other uniformed men and women of the New York Police Department, put their lives on the line every day to keep our communities safe. They run toward danger when all of our instincts tell us to run away . . . we all come together to mourn the loss of these brave souls." He directed that state flags be flown at half-staff.

On Saturday night, Patrick Lynch, the president of the New York City Patrolmen's Benevolent Association, went after de Blasio, saying: "Those that incited violence on the street in the guise of protest, that tried to tear down what New York City police officers did every day. We tried to warn it must not go on, it shouldn't be tolerated. That blood on the hands starts at the steps of City Hall in the office of the mayor," he said.

On Sunday morning, Nassau PBA President James Carver released a statement saying the killings were "a horrific and horrendous act. This kind of violence against police officers cannot be tolerated or forgotten across the nation. Our officers risk their lives everyday. My heartfelt sympathies and condolences goes out to the officers' families and all the members of the NYPD.

Carver said he supported Lynch in his " condemnation of Mayor de Blasio's anti police statements. No elected official should not fully support the men and women that serve to protect our citizens," Carver said.

Suffolk PBA president Noel DiGerolamo said Sunday that protesters against police violence had been given too much leeway.

"Clearly the lack of control and order have added to the chaos we're witnessing," DiGerolamo said, adding that he believed it was "an act of an individual with significant mental deficiencies."

"I am not going to blame any one individual, but rather a policy that has prevented certain law enforcement agencies from maintaining peace," he said.

In a letter the PBA sent to its members Sunday, he said the Suffolk PBA has offered its condolences and support to the New York City officers. "Remember your safety is paramount. Utilize any and all resources whenever needed to ensure the safety of yourself, fellow officers and the public. That is your principal objective."

In a news conference Sunday morning, the Rev. Al Sharpton said to blame the mayor and others is not what we need. The blame game will only lead to further venom."

"We are now under intense threat from those that are misguided, by those that are trying to blame everyone from civil rights leaders to the mayor, rather than deal with an ugly spirit that all of us need to fight," Sharpton said.

Former Mayor Rudy Giuliani said blaming de Blasio for the police officers' deaths went too far.

"I think it goes too far to blame the mayor for the murder or to ask for the mayor's resignation," said Giuliani on "Fox & Friends Weekend." "But I don't think it goes too far to say the mayor did not properly police the protests. He allowed the protesters to take over the streets." That, Giuliani said, led to an atmosphere that he compared to the Crown Heights riots in 1991.

"I don't think he is a bad man," Giuliani said. "I think he's pursuing the wrong policies."

The Baltimore County Police Department identified the woman shot Saturday by Brinsley as Shaneka Nicole Thompson, 29.

In a release issued Sunday, police said Thompson was in critical but stable condition after being shot in the abdomen with a 9-mm semiautomatic handgun. She is expected to survive.

Detectives have not been able to interview her yet, but officials said in the release that they hope she can provide insight into Brinsley's motivations for the police shootings.

The gunman posted a photo of a silver handgun on Instagram about three hours before the Brooklyn shooting, writing "I'm Putting Wings on Pigs Today" and using a #ShootThePolice hashtag, a police source said. In another post, he wrote: "They Take 1 Of Ours . . . Let's Take 2 of Theirs. This May Be My Final Post," the source said.

The posts also made reference to Garner and Michael Brown, both of whom were killed during encounters with police this year.

According to the release issued by police, officials believe Brinsley stole Thompson's cellphone, which helped detectives track him as he traveled to New York.

In the Sharpton news conference, Gwen Carr, the mother of Garner, who died after a police chokehold, said "I'm standing here in sorrow. The killing of these two police officers was definitely not part of our agenda. We are going in peace and we do not want the use of Eric Garner's name for violence."

Sharpton said he'll convene a meeting with members of the churches this week, including Cardinal Dolan, "to help us get past this irresponsible and reckless time we are going through. We don't need to place the blame on the mayor and create division."

Sharpton played a recording of a voice-mail message he received, which said, "Stop killing innocent people. I'm going to get you."

Garner's widow, Esaw Garner said, "It's so sad. . . . We don't want any violence connected to his name."

Garner died in July during a confrontation with NYPD officers who were trying to arrest him for selling loose cigarettes. Earlier this month, a grand jury in Staten Island failed to indict Daniel Pantaleo, the officer at the center of the case, inciting protests in New York City and cities across the nation.

Former NYPD Commissioner Raymond Kelly, speaking Sunday on "Good Morning America," said the union comments were "over the top, but obviously there is concern among the rank and file." He noted that the two cops killed were Asian and Hispanic and that "they were a reflection of the diversity of the police department."

In King's comments Sunday, he said the mayor and president were "virtually silent" about anti-police sentiments expressed during protests of killings of unarmed black men in Ferguson and Staten Island. The gunman's online postings said he was avenging the controversial deaths of two black men at police hands in Ferguson, Missouri, and Staten Island.

King said the protests fed into anti-police sentiment. "The climate appeals to fanatics and madmen," he said.

President Barack Obama, in a statement issued while he's vacationing in Hawaii, said he unconditionally condemns the slayings, The Associated Press reported.

"The officers who serve and protect our communities risk their own safety for ours every single day -- and they deserve our respect and gratitude every single day. Tonight, I ask people to reject violence and words that harm, and turn to words that heal -- prayer, patient dialogue, and sympathy for the friends and family of the fallen."

Sen. Dean Skelos (R-Rockville Centre), said in a Facebook message that "it's time for New York City's top elected City officials to begin to act like leaders in recognition of the tremendous risks police officers face every minute of every day in keeping millions of New Yorkers and those who visit the City safe."

De Blasio put out a statement characterizing the union's comment as "irresponsible and overheated rhetoric" and urging the different factions in the city to "come together.

Brooklyn Borough President Eric Adams, speaking on NBC's "Meet The Press," said, "This is not about one voice. This is about the voice of the entire city crying out for unity."

He said, regarding the relationship between the police killings and the Eric Garner protests: "We cannot mix the two. . . . Those calling for police reform were not calling for police retribution."

"Blood is not on the hands of the mayor. Blood is on the hands of a sick person," referring to the killer, Adams said,

Queens Rep. Gregory Meeks (D-St. Albans) on ABC urged calm and unity in the face of the killings.

"We don't need to divide and separate," he said. "Even at the height of the protests over Garner we said we believe that 97, 98 percent of the police officers do their jobs every day . . . let's try to bring this city together, and this country."

With Dan Rivoli, Alison Fox, David M. Schwartz, Maria Alvarez, Valerie Bauman and Deon J. Hampton.

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