The accident occurred on Monday on the Goliath ride at a Six Flags amusement park outside Atlanta, Georgia.
The cause of the accident is not yet clear. Several US media outlets, including NBC, are reporting that a person was seen falling from the roller coaster. People also had to be evacuated from the ride.
"Park staff and local authorities responded immediately, and we are fully cooperating with local authorities as they complete their investigation," Six Flags said in a statement.
