Nightmare on the N train: Inside the terrifying moments during the Brooklyn subway shooting

Blood from a gunshot wound soaked one man's pants. Another yelled that he might die. A woman pressed a wound on her lower back. Others wept.

All around Sam Carcamo were the wounded survivors of the Brooklyn subway shooting. Just minutes earlier, they had lived through a violent nightmare trapped inside a train car.

After watching bleeding and panicked passengers spill out from a smoke-filled train car on the 36th Street subway platform, Carcamo rode with those who had piled into his train car just across the platform to reach safety at the next stop.

“I saw people who were the most scared I’ve ever seen,” Carcamo, 35, an illustrator, told USA TODAY.

Since Tuesday’s New York subway shooting, which injured more than 20, emerging accounts of survivors and those who helped them paint a picture of the terrifying minutes in which riders were unable to escape a car saturated with smoke and gunfire.

WHAT HAPPENED ON THE N TRAIN: How the Brooklyn subway shooting unfolded

Smoke and gunfire fuel panic on the subway car

The chaos began early Tuesday shortly after police say a male assailant wearing a green construction vest and a gray sweatshirt boarded the second car on an N train at the Kings Highway subway station in Brooklyn, about 5 miles from the 36th Street station.

Commuters packed the train that morning, including workers headed to Manhattan, parents with children and students going to high school.

Entering the 74-foot car, commuter Hourari Benkada, 27, a hotel housekeeping manager, told CNN he boarded the train and sat right next to the gunman, who had with him a duffel bag.

Shortly before 8:30 a.m., the train approached the 36th Street station in the Sunset Park neighborhood, a bustling hub of Latino and Asian bodegas and shops.

That’s when the assailant pulled on a gas mask, set off two smoke grenades and began firing a gun at commuters, police said.

Those farther away from the attacker didn't initially realize what was happening.

Commuter Yav Montano, who estimated 40 to 50 people were in the car, told CNN the first shots sounded like “a bunch of scattered popping ... like fireworks on the floor.”

Passenger Jordan Javier said he thought the first pop was the sound of a heavy textbook dropping on the floor. Armen Hayrapetyan said in a CNN interview that he thought it might have been an electrical fire or fireworks prank and told someone not to panic.

“Then probably 20 to 30 seconds later, the shooting started,” Hayrapetyan said.

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Kenneth Foote was in the next car, he told ABC's "Good Morning America." He saw smoke first. When the train stopped in the tunnel, he said, he heard gunshots. "It was three or four quick 'Pop-pop-pops.'"

The smoke and gunfire fueled a sense of panic. Benkada said people began “bum-rushing” to the back of the car.

"This pregnant woman was in front of me, I was trying to help her. I didn't know there were shots at first – I just thought it was a black smoke bomb. She said, 'I'm pregnant with a baby!' I hugged her, and then the bum-rush continued. I got pushed, and that's when I got shot in the back of my knee,” he said, speaking to ABC-7.

Montano crouched on the floor of the car, and a woman handed him pepper spray from her purse.

Fitim Gjeloshi, 20, said he tried to confront the attacker, but he wielded an ax and pointed a gun at him, he told The Washington Post.

“All I heard was ‘boom, boom, boom,’” he said. “He just kept going.”

Juliana Fonda, a broadcast engineer in New York, was on the train in a nearby car.

“People were trying to get in and they couldn't. They were pounding on the door to get into our car,” she told the local online news outlet Gothamist, noting that people in her car wanted the conductor to get the train moving.

Hayrapetyan watched one woman with a small girl trying to escape. He said people were hurt in the panic and crush. A man next to him fell to the floor, his leg covered in blood. He struggled to breathe amid the smoke.

"That scene was really horrible,” he said in a CNN interview. “The shooting felt like it lasted for nearly 2 or maybe 3 minutes.”

'I'VE NEVER SEEN SOMETHING LIKE THAT': Brooklyn residents reconsider safety in the subway.

Train pulls into the station; shooter flees

The shooter fired 33 shots with a Glock 17 9mm semi-handgun, according to police, who believe the gun jammed. Three extended magazines were found at the scene.

When the train pulled into the station, the assailant fled.

Carcamo arrived at the station on the R train around the same time, just across the narrow platform. He watched people falling out of the doors of the other train, so he went to see what was happening.

Smoke billowed out of the N train car. People lay on the floor bleeding or scrambling to get away. Others ran across the platform and into the train Carcamo had arrived on.

Social media photos and videos show bystanders wrapping shirts around wounds. Others tended to victims slumped over in the car, some offering clothing to help stanch bleeding wounds. “Can someone help me get off?” a man said in one video reposted by The New York Times.

In all, 10 people were struck by bullets, but none of the wounds were considered life-threatening, and 19 more people were taken to hospitals for injuries ranging from smoke inhalation to shrapnel wounds, fall injuries and panic attacks, fire officials said.

Subway staff urged people to board Carcamo’s R train and ride to the next stop. The crowded train left and headed toward the 25th Street station. Among them was Javier, who said passengers wept and prayed.

For the wounded, commuters called for anyone trained in medicine. A man began aiding the wounded. Carcamo talked with several survivors, who spoke of gunshots, passengers making 911 calls and trying to get doors between the cars open.

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One woman talked about how scary it was being trapped. "There was nowhere to escape,” Carcamo said.

Detectives believe the suspect boarded the R train and rode one stop to the 25th Street station and escaped.

Carcamo and the others were evacuated from the station.

He called his mother, bought a hot chocolate and walked home.

After he posted a video on social media, Carcamo said, the FBI contacted him. Agents showed up to his apartment. He told them what he had witnessed.

Police arrested the suspect Wednesday in New York City, but police have not offered a possible motive. Local hospitals treated the injured. One hospital Tuesday evening was treating a community college student as well as children ages 16, 13 and 12.

The attack left some jittery about using the subway, an essential part of life in the city. As one victim recovered from surgery, he said he might not ride a train again.

Carcamo said he didn't feel much like riding the train on Wednesday, either.

Chris Kenning is a national news reporter for USA TODAY. Reach him at ckenning@gannett.com, or follow him on Twitter @chris_kenning.

Contributing: Kevin McCoy and Christine Fernando, USA TODAY; The Associated Press

This article originally appeared on USA TODAY: Brooklyn shooting survivors detail terrifying moments of subway attack