A chartered Boeing 737 jet with 143 people, most of whom were military personnel, on board slid off a runway and into the St Johns River in Jacksonville, Florida, while attempting to land at a military base in a thunderstorm.
There were no reports of fatalities or critical injuries. The Jacksonville Sheriff's Office said on Twitter that all 21 people who had been taken to a hospital for treatment were in good condition.
The plane, a 737-800 arriving from Naval Station Guantanamo Bay in Cuba with 136 passengers and seven crew members, crashed into the river at the end of the runway at Naval Air Station Jacksonville about 9.40pm local time, a spokesman for the Florida air base said.
"The plane was not submerged. Every person is alive and accounted for," the Jacksonville Sheriff's Office said on Twitter.
The sheriff's tweet was accompanied by two photographs showing the plane, which bears the logo of Miami Air International, resting in shallow water and fully intact.
The mayor of Jacksonville, Lenny Curry, said on Twitter that US President Donald Trump had called him to offer help.
"No fatalities reported. We are all in this together. Absorb that," Mr Curry said in a separate tweet.
A passenger on board the plane, attorney Cheryl Bormann, told CNN in an interview that the flight, which had been four hours late in departing, made a "really hard landing" in Jacksonville amid thunder and lightning.
"We came down, the plane literally hit the ground and bounced, it was clear the pilot did not have total control of the plane, it bounced again," she said, adding that the experience was "terrifying."
Ms Bormann said she hit her head on a plastic tray on the seat in front of her as the plane veered sideways and off the runway.
"We were in the water. We couldn't tell where we were, whether it was a river or an ocean."
Ms Bormann described emerging from the plane onto the wing as oxygen masks deployed and smelling the jet fuel that she said was leaking into the water.
Ms Bormann, from Chicago, said that most of the passengers were connected to the military and helped each other out of their seats and onto a wing, where they were assisted after some time into a raft.
Miami Air International is a charter airline operating a fleet of Boeing 737-800 aircraft. Representatives for the airline could not immediately be reached for comment by Reuters.
A Boeing spokesman said that the company was aware of the incident and was gathering information.