NEW YORK (WPIX) – A teenager was killed while subway surfing in New York City Monday evening, police said.

The 15-year-old boy’s head slammed into a metal beam while he rode on top of a subway train crossing the Williamsburg Bridge around 6:55 p.m., according to the NYPD. The teen, identified as Zackery Nazario, died at the scene, officials said.

The train was headed into Manhattan when the operator saw the teen on the tracks under the train and pulled the emergency brake, according to sources. Subway riders reported they saw someone climb up onto the train as it left the Marcy Avenue station, the sources said.

“We cannot stress enough how dangerous it is to ride on the outside of trains. Our hearts go out to loved ones at yet another tragic time. We implore other families to speak with their children on the real dangers of what can seem like a thrill but is too often deadly,” said NYC Transit President Richard Davey.

Nazario’s death comes less than three months after another 15-year-old was killed while subway surfing on a Brooklyn train last December.

The teen boy was riding on top of a southbound J train when he fell under the car and touched the third rail near the Marcy Avenue station in Williamsburg on Dec. 1, according to police.

Last year, the NYPD described subway surfing as an “unfortunate trending issue” that was in part fueled by social media.

“Riding on the outside of a subway car is not only illegal but incredibly dangerous. Each year we see riders, many of them teens, killed or seriously injured engaging in so-called subway surfing. We enforce rules prohibiting moving between the train cars in order to combat this dangerous behavior,” an NYPD spokesperson said in a statement on Tuesday.