Updated

A manhunt is underway in New York City for a suspect accused of donning a gas mask, setting off a smoke canister and opening fire inside a Brooklyn subway train and station during the morning commute Tuesday, injuring at least 29 people, five of whom are in critical condition.

Police identified a person of interest in the shooting as Frank James. They said he has addresses in Wisconsin and Philadelphia but his ties to New York City weren't immediately clear. 

NYPD have identified Frank James as a person of interest in the Brooklyn subway shooting. 

NYPD have identified Frank James as a person of interest in the Brooklyn subway shooting.  (NYPD)

"We are looking to determine if he has any connection to the attack," NYPD Chief of Detectives James Essig said. 

A $50,000 reward is being offered for information regarding the shooting. 

The attack began around 8:24 a.m., as a Manhattan-bound N train approached the 36th St. station in Sunset Park, Brooklyn. The suspect, described as an approximately 5-foot-5 Black male with a heavy build, is still at large and is "dangerous," New York Gov. Kathy Hochul told reporters nearly four hours after the shooting. 

The suspect's shots struck multiple people on the subway car and on the platform, New York Police Commissioner Keechant Sewell said. He was wearing a green "construction type" vest and a hooded gray sweatshirt. The suspect has not been identified by authorities, Sewell said.

Sewell said there are currently no known explosive devices on New York City subway trains and the incident is not being investigated as a terrorism incident at this time. She said no one had life-threatening injuries.

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But Mayor Eric Adams told CNN later that it was "premature" to rule out terrorism. "This is terror," Adams said. "Someone attempted to terrorize our system."

NYC people after Brooklyn subway shooting

A person is aided outside a subway car in Brooklyn, New York, Tuesday, April 12, 2022. (Will B Wylde via AP)

FDNY acting Commissioner Laura Kavanagh said 16 people were injured in the incident, 10 of whom are suffering from gunshot wounds, and five of whom are in critical condition at local hospitals.

After the press conference, Fox News learned that NYU Langone is treating a total of 20 patients in connection to the Brooklyn subway incident, up from the initial eight first reported at that hospital. 

All 20 were in stable condition, and the nature of the injuries varied from gunshot wounds to smoke inhalation, the hospital said, without disclosing how many had been shot. 

NewYork-Presbyterian Brooklyn Methodist Hospital said it is currently treating a total of three patients from the subway attack; one for a gunshot injury, another for a fracture, and the third is non-trauma-related. All three patients are in stable condition. At Maimonides Health in Brooklyn, there are five victims; three being treated for smoke inhalation and two with either shrapnel or gunshot wounds

"This individual is still on the loose," Hochul said. "We’re asking individuals to be very vigilant and alert. This is an active shooter situation right now in the city of New York." 

"We say no more, no more mass shootings. No more disrupting lives," the governor continued. "No more creating heartbreak for people just trying to live their lives as normal New Yorkers. It has to end. It ends now. And we are sick and tired of reading headlines about crime." 

Subway service was not suspended citywide after the incident, even as the suspect remains at large. 

NYC subway passengers fleeing after Brooklyn shooting

Passengers run from a subway car in a station in Brooklyn, New York, Tuesday, April 12, 2022. (Will B. Wylde via AP)

MTA CEO Janno Lieber said that although the system is disrupted, it is still running. B and W services are suspended, and D and N lines also have suspensions, with shuttle buses operating. 

"I just want to say one thing on a personal note, which is on 9/11, I stood on Fourth Avenue and watched people, New Yorkers come back from that tragedy," Lieber said. "And I watched New Yorkers help each other and storekeepers walked out and give people water. That was the same thing we saw in the platform today. We saw New Yorkers in a difficult situation, an emergency helping each other." 

Sewell said, "There are currently no known explosive devices" on the subway system, after the FDNY reportedly found several "undetonated devices" at the subway station.

Police scoured the city for the shooter and found a U-Haul in the Gravesend neighborhood with an Arizona license plate possibly connected to the shooting. The van was found just over five miles from the 36th St. station. 

A U-Haul found in connection with a shooting in Brooklyn April 12, 2022. 

A U-Haul found in connection with a shooting in Brooklyn April 12, 2022.  (Reuvain Borchardt/Hamodia.com)

A U-Haul spokesperson told Fox News that the company has been alerted by law enforcement of their search for a rental van.

NYPD officers investigating the scene near the shooting. 

NYPD officers investigating the scene near the shooting.  (Reuvain Borchardt/Hamodia.com)

"We are working closely with authorities to ensure they have any and all available information to meet their needs," U-Haul said

A senior law enforcement source later confirmed reports to Fox News that a handgun with an extended magazine was found at the scene. The source further identified the handgun as a Glock and said it was discovered inside the train where shots were fired. 

WARNING: GRAPHIC IMAGES 

NYC commuters are injured after an explosion at the 36th street subway station in Sunset Park, Brooklyn

WARNING: GRAPHIC IMAGES Sixteen people were injured in New York City subway shooting, officials confirm (Armen Armenian/Facebook)

Graphic photos of Brooklyn subway station shooting

WARNING: GRAPHIC IMAGES  Ten of the injured are suffering from gunshot wounds, officials said. (Armen Armenian/Facebook)

NYC person aided following Brooklyn subway shooting

A person is aided in a subway car in Brooklyn, New York, Tuesday, April 12, 2022. (Will B Wylde via AP)

New York City Mayor Eric Adams, who was not in-person at the Brooklyn press conference as he recovers from the coronavirus, appeared virtually on CNN afterward, reiterating that investigators do not have a positive identification of the suspect at this time. He also responded to how Sewell noted how the incident is not being considered terror-related at this point. 

"It's a preliminary investigation. This is terror of someone attempted to terrorize our system," Adams told CNN host Dana Bash. "They brought in what appears to be some form of smoke device. They discharged a weapon. And so, I don't want to be premature in justifying that this was/ was not. I think at this time, the investigators are going to do their due diligence to properly identify what happened here. And so, I think at this time, it's premature to say exactly, what happened here is still new."

NYPD Counterterrorism units responded to the scene, while additional units, including police K9s and heavy weaponry, have been deployed to subway stations around New York City, a high-ranking law enforcement source told Fox News Digital. 

The Department of Education confirmed that schools nearby were sheltering in place. New York City Schools Chancellor David C. Banks said later in the afternoon that dismissals had been completed without incident across all impacted schools. 

A graphic photo circulated on Twitter Tuesday morning showing several people lying on the blood-soaked floor of the station. One man applied pressure to what appeared to be another man’s leg wound. A red item of clothing was tied around the wound to slow bleeding. A puddle of blood was seen next to a second man grasping his cellphone, as backpacks and purses were strewn across the platform. 

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Another unverified video shared on social media appeared to be recorded by someone riding a train into the station. Crowds rushed out once the doors opened, and smoke is seen billowing through the station. 

The NYPD Transit Bureau struck down reports that subway trains were stuck between stations. 

"While there are several subways service changes, reports of trains currently stopped in tunnels are not accurate," the bureau tweeted at 10:23 a.m. ET. "All subway trains have been moved into stations. Officers are currently inspecting all stations and trains as we continue to investigate the incident at 36th St in BK." 

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NYPD News initially warned the public to avoid the 36th St. and 4th Avenue area in Brooklyn due to an investigation and said emergency vehicles and delays should be expected. 

Hochul tweeted that she had been briefed on the developing situation in Brooklyn and will work with the Metropolitan Transportation Authority (MTA) and the NYPD to provide updates once they become available. President Biden had also been briefed on the situation in Brooklyn, and White House senior staff are in touch with Mayor Eric Adams and Sewell to offer any assistance as needed, White House press secretary Jen Psaki said. 

"I'm closely monitoring the situation this morning at the 36th Street station in Sunset Park in our beloved Brooklyn," Sen. Chuck Schumer, D-N.Y., tweeted. "I'm praying for all the victims, their families, all those impacted. I’m grateful for the quick action of our first responders. To everyone in New York: Stay safe."

Fox News' Jeremy Copas, Bradford Betz and Marta Dhanis contributed to this report.