A 15-year-old boy fell to his death after playing atop a Brooklyn building on Thursday afternoon.

NBC New York reported Tyreek Riley was playing a chasing game with his friends on the roof of a four-story Crown Heights building when he tried to jump over a 10-foot gap.

Police said Riley did not make it and fell in an alleyway between the buildings below.

Cops arrived at the building on President Street, between Rogers and Nostrand avenues shortly after 4:30 p.m., but it was too late. 

Investigators said he did not live in the building.