Police are searching for a gunman who fatally shot a man aboard a Long Island Rail Road train bound for Penn Station on Monday morning.

Yusef Staine, a 20-year-old West Babylon resident, was killed at around 1:45 a.m. while on a westbound train parked at Ronkonkoma station, according to a statement provided by the MTA.

The suspected shooter was believed to be traveling with Staine, according to a preliminary investigation conducted by the Suffolk County Homicide Squad and the MTA Police Department.

The assailant fled the scene and has not been apprehended, police said.

At a press conference on Wednesday, Kevin Beyrer, head of Suffolk County's homicide squad, described the shooting as an “isolated event.”

"I'd like to stress this is not a random event,” he said, according to WABC. “No other passengers were in danger. There were only two or three other passengers on the train, they were not in danger.”

Crime on the commuter rail system increased in the last year, but remains well below its pre-pandemic average, MTA Police Assistant Chief Gary Beahan said at a board meeting last month.

Still, transit leaders have acknowledged that a spate of high profile crimes have shaken the public’s confidence in the system.

In response to concerns from riders and the transit workers’ union, the MTA agreed last month to increase its police patrols on both the Metro-North and Long Island Rail Road.