A 15-year-old boy has died after subway surfing on top of a train crossing the Williamsburg Bridge Monday night, police say.

The teen was on top of a northbound J train when he hit his head on one of the bridge's overhead beams, according to authorities.

He then fell onto the tracks and was struck by a train.

The teen was pronounced dead near the Delancey Street station on the Lower East Side of Manhattan.

In a statement, NYC Transit President Richard Davey mourned the loss of life, while also emphasizing the dangers of subway surfing.

“We cannot stress enough how dangerous it is to ride on the outside of trains,” Davey said. “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.”

In December, another 15-year-old boy died after he fell off a train and hit the third rail while subway surfing.

The teen, identified as Kavon Wooden, was subway surfing on a J train as it crossed the Williamsburg Bridge from Brooklyn to Manhattan around 11:30 a.m.

According to data compiled by the MTA, in 2022, incidents of people riding on top of, in between or anywhere outside subway cars quadrupled from the previous year in New York City.

Data shows 928 people were observed riding outside train cars in 2022, up from 206 in 2021, 199 in 2020, and 490 in 2019.

Because of the incident, service on the J and M trains was delayed but has since been restored.