The officers were "assassinated," shot "execution-style" as they sat in their patrol vehicle in the Bedford-Stuyvesant neighborhood of Brooklyn, city officials said.

Police identified the gunman as 28-year-old Ismaaiyl Brinsley.

The New York Police Department's commissioner said Brinsley was believed to have last lived in Georgia.

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On Saturday, Atlanta's WSB-TV confirmed that Brinsley had active warrants out of Cobb County. Police sources told WSB-TV that Brinsley had warrants for probation violations related to theft, firearm possession and criminal property damage charges.

Fulton County Jail records show Brinsley was booked into the jail nine times between 2004 and 2010. The offenses include simple battery, disorderly conduct, theft by shoplifting, criminal trespass, carrying a concealed weapon, possession of a knife during the commission of a felony, possession of marijuana, simple battery and terroristic threats.

NYPD Commissioner William Bratton said the two officers were shot with "no warning, no provocation."

“His last residence, as best we can determine it, is Georgia,” Bratton said.

A sea of flowers and candles marks the spot where two New York City police officers were ambushed, shot and killed.

Wenjian Liu and Rafael Ramos were shot at point-blank range while sitting in their patrol car in Brooklyn on Saturday.

New Yorkers came together to pray, remember the men and support one another on Sunday night.

WSB-TV obtained several mugshots of Brinsley, the alleged gunman. Records show him in and out of jails all across the Atlanta metro since the age of 18. Most of his arrests were in Fulton County.

Charges against him ranged from battery to theft to carrying a concealed weapon. Now, residents in Union City have learned the man accused of ambushing and murdering the officers was their neighbor.

Residents told WSB-TV's Berndt Petersen they find it unsettling to think they could have run into the man anywhere.

"That would have really bothered me.  It still does, just to know he was from here,” Union City resident Debra Shelton said.

Police say the shooting spree actually started in Baltimore, where authorities say Brinsley shot his ex-girlfriend before heading to Brooklyn.

Hours before the attack on the officers, detectives say Brinsley went on social media, where he vowed to shoot “pigs” in retaliation for the police choke-hold death of Eric Garner. The post included the hashtag “shoot the police.”  Back in Union City, residents find the violence hard to cope with and impossible to explain.

"What transpired there and his life here may be two different kinds of situations,” Union City resident Thomas Bryant said. “There’s no telling what went on with that.  It's all sad."

Records show Brinsley's Fulton County arrests were from 2004 to 2010.