A 14-year-old boy is dead after he tried to perform a dangerous stunt on the subway, according to police.

Officials said Kenny Pagan was riding between cars on the L train Wednesday night as the train was leaving the New Lots Avenue station in Brooklyn.

They say he was climbing on the metal strands between cars just after 10:30 p.m., fell onto the tracks, and was fatally struck by a Rockaway Park-bound L train.

Police are warning commuters to not put their lives at risk.

"What a terrible tragedy. I feel for him and his family," Police Commissioner James O'Neill said. "Subways are a dangerous place. I was a transit cop for a long, long time. I understand the dangers of the subway, and it's not a place to engage in behavior where you might possibly put yourself in jeopardy."

This is the third time someone died in a subway-surfing type incident since October.

Saturday, a man was killed by a train at the West 4th Street station in Lower Manhattan.

In October, a 25-year-old man fell onto the tracks while trying to climb an "F" Train in Brooklyn.

Riders who move between subway cars risk getting hit with a $75 fine.

Kenny lived at the Bay View Houses in Canarsie. Relatives and friends say he was anything but a thrill seeker, which is why they are puzzled about what happened.

"That doesn't sound like him at all," said one of Kenny's friends, Kamel Robinson. "I'm guessing it had to be pressure or something because that doesn't sound like the Kenny I know."

"We had a great conversation on Monday, but I constantly as principal say, 'What could I have said that would have changed his thinking so he would have thought first before doing it?'" said Dakota Keyes, the principal of P.S. 272.

"He was active, but he was more of an athlete-active, not [someone who would] jump between trains," one of Kenny's teachers said.

Kenny's peers remember him as a talented athlete who just earlier this week had stopped by his old elementary school to tell students and teachers there how much he missed them.