Live Updates: 16 People Are Injured, Including 10 Shot, in Attack on Brooklyn Subway

At least 16 people were injured, 10 of them by gunfire, in the subway in Brooklyn during the Tuesday morning rush, officials said, after a man released a canister of smoke and opened fire on an N train.

At around 8:24 a.m., as the train pulled into the 36th Street Station in the Sunset Park neighborhood, the man, who was wearing a construction vest, put on a gas mask before firing shots that hit people on the train and the nearby platform, said Police Commissioner Keechant L. Sewell.

The Fire Department said that five people were in critical condition, but none of them had suffered life-threatening injuries. The violent episode came amid a heightened fear of crime as New York City struggles to recover from the pandemic.

Police officers were called at 8:30 a.m. to the 36th Street station, where the D, N and R lines all stop, after receiving reports of smoke and gunshots. The shooting set off panic and chaos as riders fled from the train and the station through billowing smoke.

John Butsikares, 15, a freshman at Brooklyn Technical High School, said his ride on a northbound R train from Bay Ridge had been calm — until the train approached the 36th Street station. When the doors opened, the conductor directed passengers waiting on the platform to rush inside.

“I didn’t know what was happening,” he said. “There was just panic.”

At a news briefing, Commissioner Sewell said that the police were seeking a man with a heavy build who had been wearing a green construction vest and gray sweatshirt.

Gov. Kathy Hochul advised New Yorkers to remain “vigilant and alert,” saying “this is an active shooter situation right now in the City of New York.”

Videos posted on social media showed frightened riders pouring from a train and onto the platform as smoke filled the station. Commissioner Sewell said that no active explosive devices had been found at the scene or on subway trains.

“This is not being investigated as an act of terrorism at this time,” she said, adding that officers had not identified a motive.

Patrick Berry, 41, said he was waiting at the 25th Street station, one stop north, when an R train arrived at around 8:30 a.m. He and his 3-year-old daughter boarded, but the train didn’t move.

“Then suddenly, from the front of the train, I heard people screaming, ‘Run, run, run! Go, go, go!’ And then all these people came sprinting past our car, and I just felt like, ‘Oh my god, this is a stampede,’” Mr. Berry said. “People started pushing out from behind. So I grabbed my daughter, and we ran too.”

Toward the front of the train, three victims were being attended to by bystanders. A uniformed police officer approached, asking passengers to call 911 because his radio was not working. One teenager, who identified himself as Fitim, had a hole in his track pants that he said came from a bullet.

The area around the 36th Street Station was surrounded by investigators and cordoned off. On Fourth Avenue near 35th Street, dozens of police vehicles with flashing lights stretched down at least four blocks.

Officers blocked traffic as residents stood in small groups huddled on the sidewalk, seeking cover from the rain. At least two helicopters flew overhead.

“We saw an ambulance coming out with a stretcher with a person on it,” said Silvana Guerrero, 20, who works at nearby Sunset Bagels Cafe & Grill. “Their leg was injured — I’m not sure exactly what went on or what was going on. And then, we saw after that, two ambulances coming out, with two people, like, hopping on one leg.”

President Biden had been briefed on the shooting, officials said. Mayor Eric Adams, who tested positive for Covid-19 on Sunday and is currently isolating, was also monitoring the situation.

“We will not allow New Yorkers to be terrorized, even by a single individual,” Mr. Adams, a former police officer, said in a video message. “N.Y.P.D. is searching for the suspect at large, and we will find him.”

Eight people with injuries from the shooting were being treated at NYU Langone Hospital-Brooklyn, said a spokeswoman for the hospital system, Lisa Greiner. Their injuries included gunshot wounds and smoke inhalation; all eight were in stable condition.

Suzanne Tammaro, a spokeswoman for Maimonides Medical Center in Brooklyn, said that five people were being treated there, two of them with gunshot wounds. NewYork-Presbyterian Brooklyn Methodist Hospital said it was treating three patients injured in the shooting.

Shootings in New York City have increased this year, and the uptick in violent gun crime has been a central focus for Mr. Adams since he took office in January. Through April 3, shooting incidents rose to 296 from 260 during the same period last year, according to Police Department statistics.

The increase comes after gun violence hit historic lows in 2018 and 2019, and the city still remains safer than in previous years. But as New Yorkers emerged from the shutdowns that marked the start of the pandemic, many found the city more dangerous than when the coronavirus swept across New York in the spring of 2020.

Mr. Adams has sought to reassure residents and recently deployed about half a dozen new anti-gun police units. The Police Department has also started focusing on so-called quality-of-life violations, recalling the city’s embrace of “broken windows” policing — the stricter enforcement of low-level offenses in an effort to prevent more serious crimes.

But New York has faced a string of shootings in recent days that have highlighted the challenges in halting a rise in violent crime that is taking place in cities cross the country.

“No more mass shootings. No more disrupting lives. No more creating heartbreak for people just trying to live their lives as normal New Yorkers,” Ms. Hochul said on Tuesday. “It has to end, it ends now.”

The mayor has taken a similar policing approach in the subway system, where transit leaders had for months before his tenure been seeking more help in policing trains and stations.

The Metropolitan Transportation Authority, which operates the system, has said that fears over safety have diminished confidence and kept riders off the subway, which is considered a lifeblood of the city and a key to its economic rebound.

Reporting was contributed by Jonah E. Bromwich, Emma G. Fitzsimmons, Joseph Goldstein, Andrew Hinderaker, Sadef Ali Kully, Ana Ley, Andy Newman, Chelsia Rose Marcius and William K. Rashbaum.