A motive in the attack remains unknown, but two law enforcement sources told CNN James called in the tip to Crimestoppers that led to his capture Wednesday.
“This case was quickly solved using technology, video canvassing, and then getting that information out to the public,” New York Police Department Chief of Detectives James Essig said.
Ten people were shot and 19 more were injured by smoke inhalation, falling down or had panic attacks, officials said.
Here’s what we know about the attack.
Gunman fired into a crowd 33 times, police say
Commuters told investigators that before the train arrived at the station, a gunman in one of the cars opened two smoke grenades, brandished a 9 mm handgun and fired multiple times, police said. At least 33 shots were fired, and 10 people were shot – seven men and three women – Essig said.
Two officials believe the gun jammed during the shooting, they said.
The attack is not being investigated as an act of terrorism, but authorities have not ruled anything out, she said.
Five of the victims were students commuting to school, New York Gov. Kathy Hochul told reporters outside Maimonides Medical Center. She met with a 12-year-old, a 13-year-old, a 16-year-old and two 18-year-olds at the hospital, which is the only pediatric trauma hospital in the area, she said.
U-Haul van offered some clues
Both items helped investigators find a U-Haul van Tuesday afternoon near the station in the Gravesend section of Brooklyn, police said.
Investigators also found a Glock 9 mm handgun, three extended magazines, two detonated smoke grenades, two non-detonated smoke grenades and a hatchet, Essig said.
The 9 mm Glock recovered at the crime scene was purchased by James in 2011 in Ohio, Essig said. It was found with scratch marks on its serial number, according to court documents. Prosecutors said they believe the marks “appear to reflect that an attempt was made to deface the serial number.”
The van was recovered and cleared by the NYPD’s bomb squad, police said. It was due to be taken to a forensic location where federal and local authorities can go through it in a controlled environment, a senior law enforcement official told CNN.
Suspect seen in videos talking of violence
James and his family did not immediately respond to CNN’s request for comment. CNN has also reached out to his federal defender, Mia Eisner-Grynberg, for comment.
“He is known to us, and has ties in Wisconsin, Ohio, Pennsylvania, New Jersey, and New York City,” Essig said.
The NYPD recovered video of James entering the Kings Highway subway station in Brooklyn with the same black cart later recovered on the crime scene, Essig said.
This station is three blocks from where the U-Haul van – which was rented by James in Philadelphia – was discovered, Essig added.
The van was rented Monday from a U-Haul store in Philadelphia, company records obtained by CNN show. The U-Haul reservation was made April 6 and scheduled to be picked up Monday at 2:01 pm, the rental agreement obtained by CNN shows. The van was supposed to be rented for two days, according to the reservation.
The records show James rented the van using a Wisconsin license with a Milwaukee address.
Based on photographic evidence, police believe that after the shooting, James boarded an R train, went one stop up, and exited at 25th Street, Essig said.
Police tracked James, and his last known whereabouts was the 7th Avenue and 9th Street subway station, Essig said.
“Following the tragic event in New York City, our Trust and Safety team identified and terminated a YouTube channel associated with the suspect, in accordance with our creator responsibility guidelines,” YouTube spokesperson Jack Malon said in a statement.
YouTube confirmed Wednesday it removed the account that appeared to be connected with James.
James has nine prior arrests in New York between 1992 to 1998, including possession of burglary tools, criminal sex act and theft of service, Essig said. Criminal tampering was also seen on his New York arrest record.
In New Jersey, James was previously arrested in 1991, 1992 and 2007 for trespass, larceny and disorderly conduct, Essig said.
Witness accounts recall frantic scene
Images captured by people at the scene and witness accounts piece together a picture of the panic and chaos that ensued when shots began to ring out in the smoke-filled train car.
In one video, people can be seen rushing off the subway train after it pulled into the 36th Street subway station.
Smoke pours out of the car where the shooting took place, and people can be heard screaming, that video shows. Someone helps an injured and bleeding person off the train, and another man is seen hobbling off the train shortly afterwards.
Images taken by others at the scene show the subway platform streaked with blood and people sitting and lying on the train platform following the attack.
The photo gallery below contains graphic images. Viewer discretion is advised.
Hourari Benkada, 27, believes he was sitting next to the shooting suspect on the N train, he said. The man, he said, had a duffel bag and was wearing a Metropolitan Transportation Authority vest. Then the man let off a “smoke bomb,” and Benkada and other passengers tried to rush to the other end of the car, he said.
Benkada was focused on helping a pregnant woman, whom he feared would get hurt as people rushed to the front of the car, when he got shot in the back of his knee, he said, describing it as “the worst pain of my entire life” . “
The shooting started about 20 seconds after the train took off, Benkada said.
“I feel shocked, I feel shaky, I do not know if I can ever ride a train,” Benkada, a lifelong New Yorker and a housekeeping manager at The New Yorker hotel, said after coming out of surgery.
The bullet hit him in the back of his knee and came out the other side, he said. Doctors told him the bullet grazed his kneecap. He is expected to walk on his own after several weeks on crutches.
Benkada heard other people in pain but could not see them or the suspect because of the smoke, he said.
Claire Tunkel, 46, took off her jacket and tied it around the leg of a man who suffered a gunshot wound, she told CNN. Tunkel, who went to the hospital for smoke inhalation, said several victims were lying on the floor of the subway platform after the train arrived at the station.
“One of the guys who was shot, his leg was bleeding pretty bad, so I took off my jacket and tied it around his leg,” she said.
Tunkel was in the subway car where the shooting took place and described the scene as chaotic. While she could not see anything because of the smoke, she said she heard people crying out for help and others who said they were bleeding.
“You could not see anything, but you could feel it,” she said. People were rushing to the front of the car, and some fell to the ground, she noted. “You could feel the bodies.”
CNN’s Jason Hanna, Eric Levenson, Shrif Paget, Caroll Alvarado, Laura Ly, Kristina Sgueglia, Paul Murphy, Brynn Gingras, Shimon Prokupecz, Pervaiz Shallwani, Mark Morales and Maureen Chowdhury contributed to this report.