(CNN) -- A 19-year-old man has been arrested in what prosecutors said was the "execution-style" killing of a Lakewood, New Jersey, police officer, authorities said Sunday.
Jahmell Crockam was in custody following an arrest overnight, said Thomas Hayes of the Ocean County, New Jersey, Prosecutor's Office.
Ocean County Prosecutor Marlene Lynch Ford told reporters authorities received information that Crockam had holed up in an apartment in Camden, New Jersey, about 65 miles southwest of Lakewood. A New Jersey State Police tactical team, along with other agencies, arrested him without incident, she said.
Crockam is charged with murder and illegal possession of a firearm. He is a suspect in the Friday afternoon death of officer Christopher Matlosz, 27. Matlosz had pulled up next to a man on foot while in his patrol car, and was talking with him.
"The individual stepped back suddenly, pulled out a handgun and shot the officer three times," Ford said Saturday. "The officer's weapon was still in his holster. That is how quickly it happened."
Police were still investigating whether Matlosz knew the suspect and what the two were discussing when the shooting occurred. Witnesses have told police that the exchange between the officer and the gunman appeared calm before the shooting.
Authorities were also investigating whether anyone else was involved in the incident, Ford said. She said it would be premature to state whether Crockam is affiliated with a gang.
Thomas Hayes of the Ocean County Prosecutor's Office said Sunday an arraignment time for Crockam had not yet been set, as Monday is a federal holiday.
Matlosz "was one of our most popular officers. He was dedicated to his job," Lakewood Police Chief Robert Lawson said. "He was the best of us."
Matlosz had worked for the police department for more than four years and was engaged to be married.
In a statement released by the police department Saturday night, his fiancee, Kelly Walsifer, said Matlosz was "my best friend and soul mate. ... In the last four years, we both lived our life to the fullest. He was my life and my world. He made me laugh, he made others laugh and we have been surrounded by the best of friends and co-workers throughout our time together."
Walsifer said Matlosz had just lost his father, "and now it brings me some peace to know that he is with him."
CNN's Miguel Susana and Cheryl Robinson contributed to this report.