Multiple people were shot Tuesday morning in an incident involving a northbound N train in Brooklyn, New York, the city fire department said. According to multiple law enforcement sources briefed on the investigation, preliminary information indicated a suspect fled wearing a construction vest and a gas mask.

Fire personnel responding to reports of smoke at the 36th Street station in Sunset Park found multiple people hurt, but aside from five who were shot, there were no details on what the other injuries entailed.

Photos and video from the scene showed people tending to bloodied passengers lying on the floor of the station and the air filled with smoke. Fire and police officials were investigating reports that there had been an explosion, but the police department tweeted that there were “no active explosive devices at this time.” Multiple smoke devices were found on the scene, mayoral spokesperson Fabien Levy, who confirmed the initial shooting injury count, said.

“My subway door opened into calamity. It was smoke and blood and people screaming,” eyewitness Sam Carcamo told radio station 1010 WINS, saying he saw a gigantic billow of smoke pouring out of the N train once the door opened.

Trains servicing that station were delayed during the morning rush hour.

The incident happened on a subway line that runs through south Brooklyn in a neighborhood about a 15-minute train ride to Manhattan. Local schools, including Sunset Park High School across the street, were locked down.

Gov. Kathy Hochul said in a statement she had been briefed on the situation and her office would work with the transit authority and police department as the investigation continued.

The shootings came as New York City has faced a string of shootings and high-profile incidents in recent months, including on the city’s subways. One of the most shocking came in January when a woman was pushed to her death in front of a train by a stranger.

New York City Mayor Eric Adams has made cracking down on crime a focus of his early administration, pledging to send more police officers into subway stations and platforms for regular patrols. It wasn’t immediately clear whether officers had already been inside the station when the shootings occurred.