At an early evening news briefing, police named a “person of interest” in the investigation as Frank James, who investigators believed had rented the U-Haul vehicle.

Police said they recovered the key to the van at the crime scene and it had been rented in Philadelphia. Officials said James had addressed in Philadelphia and Wisconsin.

Sewell said the attack was not being investigated as terrorism, but that she was “not ruling out anything”. The shooter’s motive was unknown.

Sitting in the back of the train’s second car, the gunman tossed two smoke grenades on the floor, pulled out a Glock 9 mm semi-automatic handgun and started firing, Essig said. A rider’s video shows a person raising an arm and pointing at something as five bangs sound.

Passengers in the smoke-filled car pounded on the door to an adjacent car, seeking to escape, rider Juliana Fonda, who was in that adjoining car, told the news site Gothamist. Fonda is a broadcast engineer for Gothamist’s owner, public radio station WNYC.

Investigators believe the shooter’s gun jammed and kept him from firing more, said two law enforcement officials who weren’t authorised to discuss the investigation and spoke on condition of anonymity.

Essig said police found the weapon, along with extended magazines, a hatchet, detonated and undetonated smoke grenades, a black garbage can, a rolling cart, gasoline and the key to a U-Haul van.

That key led investigators to James, the detective chief said. The van was later found, unoccupied, near a subway station where investigators determined the gunman entered the train system.

Rambling, profanity-filled YouTube videos apparently posted by James, who is Black, are replete with Black nationalist rhetoric, violent language and bigoted comments, some of them directed at other Black people. One, posted on April 11, criticises crime against Black people and says drastic action is needed to change things.

Several videos mention New York’s subways, and Adams is a recurring theme.

A video uploaded on February 20 says the mayor and governor’s plan to address homelessness and safety in New York City’s subway system “is doomed for failure” and refers to himself as a “victim” of the mayor’s mental health program. A January 25 video criticises Adams’ plan to end gun violence.

The attack unnerved a city on guard about a rise in gun crimes and the ever-present threat of terrorism. It left some New Yorkers jittery about riding the nation’s busiest subway system and prompted officials to increase policing at transportation hubs from Philadelphia to Connecticut.

“This individual is still on the loose. This person is dangerous,” Governor Kathy Hochul warned at a midday news conference.

The Metropolitan Transportation Authority announced last autumn that it had put security cameras in all 472 subway stations citywide, saying they would put criminals on an “express track to justice”.

But at the station where the train arrived, the cameras apparently malfunctioned.

MTA system chief Janno Lieber told TV interviewers he didn’t know why the cameras weren’t working. But he said police had “a lot of different options” from cameras elsewhere on the subway line to get a glimpse of the shooter.

In Menlo, Iowa, President Joe Biden praised “the first responders who jumped in action, including civilians, civilians, who didn’t hesitate to help their fellow passengers and tried to shield them.”

Adams, who is isolating following a positive COVID-19 test on Sunday, said in a video statement that the city “will not allow New Yorkers to be terrorised, even by a single individual.”

Adams, a Democrat a little over 100 days into his term, has made cracking down on crime — especially on the subways — a focus of his early administration, pledging to send more police officers into stations and platforms for regular patrols. It wasn’t immediately clear whether officers were already inside the station when the shootings occurred.

AP, Reuters

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