An ex-boyfriend has been charged on a second-degree murder warrant in the stabbing death of a woman and the fatal beating of her 2-year-old son in their North Bay Shore home, Suffolk police said Monday.

Jerry A. Lewis, 24, lived part time in the same South Cardinal Court apartment as the two victims and used to baby-sit the boy, police said. He was arrested Sunday in Laurel, Md., after turning himself in to local police. Suffolk police said he was charged on a Suffolk arrest warrant in the deaths of Shakeela Planter, 21, and her son, Jaiden.

Lewis' extradition hearing is scheduled for Tuesday before a Prince George's County judge, said Jim Collins, a spokesman for Laurel police. If Lewis waives it, Suffolk authorities can bring him back to Long Island, he said.

Lewis walked into the Laurel police station at 7:40 p.m. Christmas Eve and "said he had committed murder in New York and that he wanted to turn himself in," said Collins. Officers took Lewis into custody and notified Suffolk police, Collins said.

Laurel police said they believe that Lewis had been visiting his mother, who lives near the police station, for just a day or two before turning himself in.

Suffolk police suspect Planter was killed early on Dec. 18, not long after her Saturday night shift in the dietary department at Huntington Hospital.

advertisement | advertise on newsday

Homicide squad commander Det. Lt. Gerard Pelkofsky said the two had formerly been "boyfriend/girlfriend" but their relationship was now "up in the air." They had a dispute that led to the deaths, but it's unclear what the argument was about. Pelkofsky declined to comment on any murder weapon.

According to police, co-workers tried to reach Planter unsuccessfully as Lewis fled in her SUV.

"Co-workers that she normally would be in contact with reported to the security department that they haven't seen and haven't been able to get in touch with her," said Pelkofsky. "There were also comments on Facebook that [said], 'Please call me, I haven't heard from you.' "

After the slayings, Lewis drove Planter's car to New Jersey to visit a sister, then drove back to Long Island, where he abandoned the car at the Tanger Outlets at The Arches in Deer Park, police said.

There were conflicting accounts on how Lewis got to Laurel. Suffolk police said he traveled by train, but Laurel police said he took a bus from New York City.

Planter's landlord, who lives upstairs in the North Bay Shore house, went to check on her in the basement apartment and found her body about 5:15 p.m. Friday, police said.

She had been stabbed several times, and Jaiden, who was "viciously beaten," was found during a police search, Pelkofsky said. "The baby was ultimately put in a plastic bag and put in a freezer," he said. "The female was bound and wrapped, and left on the bed" after she died.

Pelkofsky said Planter, who leased the apartment, had lived there for about six months. Lewis, who came from Jamaica in March 2010, also had lived there for at least part of the time since Labor Day.

Planter was born in Jamaica and held a nursing home job before working at the hospital, police said. Lewis was not Jaiden's father, but took care of the boy.

"He was baby-sitting for Jaiden," Pelkofsky said. "He was helping out in the house, but we don't know if it was purely platonic or if it was a relationship."

advertisement | advertise on newsday

There had been no prior reports of domestic violence at the apartment, and Lewis did not have a criminal record, police said.Pelkofsky said this was a very hard case for police to handle, particularly near the holidays.

"Detectives were, of course, emotionally involved in this case. I was at the morgue and people in the morgue had tears in their eyes and they deal with death all the time. It's particularly vexing and really affects your moral fiber when something like this happens."

Rosmeri De Los Santos, wife of the landlord who had found Planter and her son, spoke to reporters at one point and appeared shaken and upset. "She was amazing. She was an amazing person," De Los Santos said of Planter, adding of Jaiden: "I loved him."

One of Planter's neighbors said she'd heard a woman screaming Saturday night when police and detectives were at the crime scene.

"I heard a woman screaming like crazy," Carolina Zuluaga, 28, who lives behind Planter's apartment, said Sunday.

advertisement | advertise on newsday

When told that a woman and her toddler were found dead in the house Friday, she said, "Oh my God. That is horrible and very scary. The street over here is very dark. It could've been anybody."

Neighbors said they didn't know Planter well.

"Nobody really associates with each other," said Teddy Burgos, 60, who lives across the street. "If you happen to see anybody, it's just by coincidence."

With Ellen Yan, Aisha Al-Muslim and Kery Murakami