"I thought it was a shooter," train rider Leslie Bradshaw said. "I didn't know if it was a bomb."
It happened around 9:30 a.m. on an F train at 14th Street as the train began moving, with the chaos ensuing at the 23rd Street Station.
The suspect fled the scene, but it is unclear at which station.
"You just get kind of scooped up in it," Bradshaw said. "And then we just started jumping from car to car as a big unit."
The NYPD and FDNY were on the scene investigating, and authorities are asking anyone who witnessed the incident to call 911 with any timely information.
Transit personnel was assisting customers.
"This is criminal, dangerous and abhorrent behavior," NYC Transit President Andy Byford said. "We are working with the NYPD to ensure whoever did this is brought to justice."
Authorities believe a group of teenagers were in the last car on the northbound F train, and one of them threw the firecracker on the train floor.
"Some mindless idiots set up a large firecracker on a train in the rear car of the F train," said Byford, adding that the incident is a felony. "We are going to nail them, because that is stupid, reckless, mindless moronic behavior. It has no place on the New York City subway system. It caused unnecessary consternation to people, and it caused a big delay... you are an idiot, and you deserve to be brought to justice."
There were no serious injuries, but a 52-year-old woman was taken to Bellevue Hospital after apparently twisting her knee in the stampede.
Others were so frightened, they left valuables behind. Police are looking for the owners.
"I looked down and then saw somebody's shoe," Bradshaw said. "I saw high-heels. I saw a laptop. I saw a purse. So it looks like people were just abandoning whatever they had, just went for it...It was that serious. It was not something, it felt like a catastrophe, the things you see in the movie."
There does not appear to be a link to terrorism or anything nefarious, but subway riders quickly took to social media.
This is the panic in the train pic.twitter.com/b6j7RDwRkT— Simply-_-Dbest (@iiiM_Steven) May 31, 2019
Just fled a northbound F train with all the passengers. Complete panic. Unclear of the issue, but full stampede moving from car to car - chaos. We all ran off at the 23rd Street stop. Thankful to be safe and hope everyone else is, too. @MTA #MTA @NYCTSubway— Leslie Bradshaw🐢 (@LeslieBradshaw) May 31, 2019
One thing is for sure: New Yorkers don’t stand around and wait to figure out what’s going on. They M-O-V-E.— Leslie Bradshaw🐢 (@LeslieBradshaw) May 31, 2019
More from scene of #Ftrain attack, everyone disembarked from 23 St. people were running through train cars trying to escape. One woman lost a shoe, carnage of spilled coffees, groceries, etc. pic.twitter.com/MU5RXKPkY5— Amelia Vogler (@Amelia_Vogler) May 31, 2019
Just got caught up in a terrifying stampede on the NY subway. People came flooding in from the next carriage screaming and set off a chain reaction of fear. Apparently someone let off a firecracker or something. Shoes, bags, screaming.Seems most people ok. Someone broke an ankle.— Dave Calhoun (@davecalhoun) May 31, 2019
There were several subway delays and diversions as a result, but service has since returned to normal.
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