The fatal shooting of Nassau County police Officer Arthur Lopez struck at the heart of a force mourning the three other officers killed in the line of duty since last year.
The death left the tight-knit department struggling with sorrow, frustration and anger.
"To say this is a difficult time would be an understatement," James Carver, president of the Nassau Police Benevolent Association, said in a news conference Tuesday hours after Lopez, 29, was shot by an ex-convict from Queens. "What price do you put on . . . what every single officer does out there every single day in Nassau County?"
Hundreds of Nassau police, including Lopez, on Monday attended the funeral for Officer Joseph Olivieri, killed in an early morning crash Thursday on the Long Island Expressway.
"We didn't even begin to recover," Carver said Tuesday night. "A lot of guys are hurting here right now. We need time to heal."
Still painfully fresh in their memories are the funerals for officer Michael J. Califano, killed in February 2011 when a truck slammed into his patrol car on the LIE, and Geoffrey J. Breitkopf, fatally shot at a Massapequa Park home in March 2011.
"Once again, it's a tragic day for the Nassau County Police Department and Nassau County," police Commissioner Thomas Dale said. "This has been a devastating week."
Nassau police Public Information Officer Steven Zacchia summed up the department's mood: "It's like the loss of a family member."
Every officer in a police department, and even those in other agencies, feels some trauma and "varying degrees of guilt" when an officer is killed, said Vincent Henry, director of the Homeland Security Management Institute at LIU Riverhead and a retired 21-year veteran of the NYPD. He has studied the impact of line-of-duty deaths for his book "Death Work: Police, Trauma, and the Psychology of Survival."
Because of the intrinsic danger of their work, officers come to see other members of the force as an extended family where members need to rely on each other, Henry said. During a period of grief after an officer's death, others on the force will become aware of their own mortality, he said.
"There's bound to be a lot of anger, confusion and grief mixed up in how officers react to this," Henry said.
Officers will lean on each other to get through the loss, but the department may have to take measures to offer counseling to those closest to the officer killed, said John A. Eterno, a former NYPD captain and associate dean at Molloy College in Rockville Centre. "It's going to be devastating, especially to a suburban department like Nassau County, where many of the officers know each other," he said.
Officers in Lopez's unit saw counselors most of Tuesday.
Nassau County Executive Edward Mangano appeared emotional as he spoke at the news conference, saying Lopez's killer left "the people of Nassau County, his parents, his loved ones, and our county" grieving.
Mangano ordered that government flags, which were to be flown at half-staff until Nov. 18 in memory of Olivieri, remain lowered until Dec. 19 to honor Lopez, of Babylon Village.
Harvey Kushner, head of the Department of Criminal Justice at LIU Post in Brookville, said the Nassau deaths underscore the dangers faced by police officers.
"Every day they go to work they put their lives on the line," Kushner said. "The public doesn't always realize that the police officers are traumatized by these incidents as well."
With Robert Brodsky
and Tania Lopez