Jeremy Sanchez, a member of the gang OY, confessed to shooting Kenneth Archbold, 19, in Manhattan during the summer, the New York Daily News said.
"We started chasing them," the newspaper said Sanchez told investigators when he was arrested Aug. 29. "I went after one, but he got away. When I came back [Archbold] was being beaten up. I had a .380 pistol and I shot him three times."
Sanchez recalled the slaying after he was arrested for an armed push-in burglary, the Daily News said.
Critics denounced director Termaine Brown's gritty independent picture "Toddlers" when it was released on DVD earlier this year, saying it glorified gang life.