Travelers aboard American Eagle Flight 4817 had reported "suspicious and erratic behavior" from another passenger, who was taken into custody shortly after the plane touched down. Authorities announced Sunday that the man was not charged and determined there was no criminality.
Investigators with the FBI and Port Authority of New York and New Jersey characterized the incident as a "misunderstanding."
"Some people were yelling, 'bomb.' Some people were yelling, 'fire.' It's very unclear what's happening. Most people were just saying, 'Run. Go,'" said Abigal Kunkle, a passenger on board the flight from Indianapolis to New York.
After landing, the pilot halted the airplane on the taxiway short of its intended gate around 3 p.m. local time.
The plane was evacuated, and video posted on social media showed a man spread-eagled face down on the runway asphalt as a pair of emergency personnel knelt beside him. The man did not appear to resist.
Other passengers appeared bewildered by the scene as they were escorted away from the plane. Some were bloodied amid the chaos.
Our sister station WABC-TV spoke to Flight 4817 passenger Sawad Khuja, who said the man was sitting about five or six rows behind him and heard a woman say, "Don't do that, don't do that."
It's not clear what she was referring to, but Khuja said panic ensued immediately afterward.
"Everyone was just shoving and pushing, jumping out of the airplane [after landing]. They lost the slide, people were falling off the slide left and right. People were bleeding. It was crazy," he said.
In an email, a spokesperson for the U.S. Department of Homeland Security said "nothing harmful was on the aircraft."
Republic Airways said Flight 4817 was operating under the banner of American Airlines and that the onboard incident occurred near the end of the flight, a roughly 2-hour trip from Indianapolis to LaGuardia.
"Upon exiting the active runway, the aircraft stopped on a taxiway and conducted a precautionary emergency evacuation," Republic Airways said in a statement. "Law enforcement and first responders met the aircraft and the passenger involved in the incident has been taken into custody."
There were no injuries to any of the 78 passengers and four crew members aboard the flight.
The Associated Press contributed to this report.