A man who posted social media videos decrying the US as a racist place awash in violence and recounting his struggle with mental illness has been arrested, a day after 10 people were wounded in an attack on a New York train.

Frank R James, 62, was taken into custody in Manhattan’s East Village neighbourhood, according to law enforcement officials who spoke to The Associated Press on Thursday morning.

Further details weren’t immediately available.

Tweet from @business

Police had initially said that Mr James was being sought for questioning because he had rented a van possibly connected to the attack in Brooklyn, but weren’t sure whether he was responsible for the shooting.

Mayor Eric Adams said in a series of media interviews that investigators had upgraded Mr James to a suspect, but did not offer details beyond citing “new information that became available to the team”.

The gunman sent off smoke grenades in a crowded subway car and then fired at least 33 shots with a 9mm handgun, police said.

Five gunshot victims were in critical condition but all 10 wounded in the shooting were expected to survive. At least a dozen others who escaped gunshot wounds were treated for smoke inhalation and other injuries.

The shooter escaped in the chaos, but left behind numerous clues, including the gun, ammunition magazines, a hatchet, smoke grenades, petrol and the key to a U-Haul van.

That key led investigators to Mr James, a New York City-area native who had more recent addresses in Philadelphia and Wisconsin.

His van was found near a station where investigators determined the gunman had entered the subway system.

Investigators believe Mr James drove up from Philadelphia on Monday (local time) and have reviewed surveillance video showing a man matching his physical description coming out of the van early Tuesday morning, the official said.

Tweet from @ABC

Other video shows Mr James entering a subway station in Brooklyn with a large bag, the official said.

In addition to analysing financial and telephone records connected to Mr James, investigators were reviewing hours of rambling, profanity-filled videos he had posted on YouTube and other social media platforms.

In one video, posted a day before the attack, Mr James criticises crime against Black people and says drastic action is needed.

“You got kids going in here now taking machine guns and mowing down innocent people,” Mr James says.

“It’s not going to get better until we make it better,” he says, adding that he thought things would only change if certain people were “stomped, kicked and tortured” out of their “comfort zone”.

In another video he says, “this nation was born in violence, it’s kept alive by violence or the threat thereof and it’s going to die a violent death. There’s nothing going to stop that.”

-AAP