Law enforcement officers stand guard at the scene of a shooting at a subway station in the Brooklyn borough of New York City, New York, U.S., April 12, 2022.
Law enforcement officers stand guard at the scene of a shooting at a subway station in the Brooklyn borough of New York City, New York, U.S., April 12, 2022. Reuters / EDUARDO MUNOZ

Police and federal agents searched into the early hours of Wednesday for a man who set off smoke bombs and sprayed fellow passengers with gunfire aboard a New York City subway car, injuring more than 20 people before he fled the scene.

The attack erupted during the Tuesday morning commuter rush as the Manhattan-bound N line train was pulling into an underground station in Brooklyn's Sunset Park neighborhood, the latest burst of seemingly random violence that has plagued the city's transit system in recent years.

Police said 10 people were struck directly by gunfire, five of them hospitalized in critical but stable condition, while 13 others suffered respiratory distress or were otherwise injured in the crush of frantic riders fleeing the smoke-filled subway car.

Some injured passengers collapsed as they poured onto the platform of the 36th Street station.

All of the victims were expected to survive their injuries, police said in an evening news conference, in which authorities also offered rewards totaling $50,000 for information leading to the arrest of the gunman they believed acted alone.

On Wednesday, New York Police Department said a man identified as Frank James is now a suspect in the shooting. Initially the police said he was viewed only as a "person of interest," having been linked by evidence to the crime scene. Authorities did not say why James was now considered a suspect.

James was first linked to the scene after police found a U-Haul van parked on a Brooklyn street. James was believed to have rented the vehicle in Philadelphia. Police said they recovered the key to the van at the crime scene, and that James had addresses in Philadelphia and Wisconsin.

Attempts by Reuters to reach any of the phone numbers associated with James were unsuccessful.

Adams, in interviews on Wednesday on MSNBC and CNN, vowed to bring the suspect to justice and told New Yorkers to stay vigilant as they go about their day.

"It's clear that this individual wanted to create terror and violence," he said. "We know that he wanted to bring terror to come on the (subway) system with a gas mask, with a gun, several clips as well as throwing a smoke bomb."

New York Police Department (NYPD) Commissioner Keechant Sewell told reporters on Tuesday that the shooting was not immediately being treated as an act of terrorism.

"You can't let one person alter your life, gotta keep on, keep on going," Michael Torres, a FedEx worker, said to Gothamist, a local news source, as he boarded a train on Wednesday morning at the 36th St. station.

There was no known motive for the attack, but investigators found a number of social media posts linked to an individual named Frank James that mentioned homelessness and the New York City mayor, Sewell said.

The subway assailant was described by police from eyewitness accounts as a man of heavy build, wearing an orange vest, a gray sweatshirt, a green helmet and surgical mask.

The commissioner said the attack began in the train car as it was about to enter the station. The gunman removed two canisters from his bag and opened them, sending smoke throughout the train car.

Police said the man then fired 33 rounds from a Glock 9 mm semi-automatic handgun, which was later recovered along with three extended ammunition magazines, a hatchet, some consumer-grade fireworks and a container of gasoline.

The gun apparently jammed in the midst of the shooting, potentially preventing a higher casualty toll, CNN and local media outlets reported, citing law enforcement sources.

New York City has seen a sharp rise in violent crime during the pandemic, including a string of seemingly random attacks on its subways. The transit violence has included a number of attacks in which passengers were shoved onto the tracks from platforms, including a Manhattan woman whose murder was seen as part of a surge in hate crimes against Asian Americans.

Adams, who has vowed to improve subway safety by increasing police patrols and expanding mental health outreach programs, called Tuesday's incident "a senseless act of violence" and pledged to double the number of officers assigned to subway security.

New York Governor Kathy Hochul pledged "the full resources of our state to fight this surge of crime, this insanity that is feeding our city."