A troubled teen menace  was nabbed Tuesday for fatally gunning down a 14-year-old boy on a scooter in Queens last month, sources said — revealing the killing involved an online spat, not a robbery.

Police busted the 17-year-old suspect — a Crips gang associate — at his home around 11:30 a.m. and charged him with murder for blasting Malakai Adams in the back and then zooming off on the victim’s scooter  Sept. 21 in Edgemere, according to cops.

Law-enforcement sources at the time described the shooting as a possible scooter robbery gone wrong but said Tuesday that the two teens had been involved in an online argument.

The alleged killer, whose identity was not released because of his age, was previously caught with a loaded .22-caliber pistol in July 2025 after cops stopped him for shooting fireworks at passers-by, sources told The Post.

The outcome of that case is not public because of his age.

Police sources said the suspect  is associated with the Crips gang but is not in the NYPD’s official gang database.

Last month’s violence exploded when the killer ran up to the scooter-riding Adams with a gun around 3:40 p.m. behind Ocean Bay Apartments on Beach Channel Drive, an area locals say is plagued with crime.

Adams tried to ride away before he was shot. After firing at the 14-year-old old, the suspect  grabbed the victim’s scooter and fled eastbound on Norton Avenue, police said.

Adams was rushed to Long Island Jewish Hospital, where he later died.

His mother, Alexis Credle, remembered her “beautiful son” in an online fundraiser for her son’s burial.

“My baby, you were taken from me far too soon,” the devastated mom wrote.

“I will carry you in my heart every single day for the rest of my life. I love you more than words could ever say.”

His teen killer was awaiting arraignment Tuesday.