A fallen tree branch obstructed and derailed a roller coaster at Six Flags Magic Mountain in Valencia, California Monday night.
22 passengers, including four who suffered injuries, were stuck in a "precarious position" 40 feet in the air on the "Ninja" coaster for more than two hours, Los Angeles County Fire Department dispatch supervisor Michael Pittman told the Los Angeles Times.
All riders were safely evacuated by 8:30 p.m.. A pair of passengers were taken to a local hospital as a precaution, but their injuries appear to be minor.
"The safety of our guests and employees is our number one priority and as a precaution, the ride will remain closed until a thorough inspection of the area is complete," park officials said in a statement.
Ninja opened in 1988 and takes up to 28 passengers on a ride that tops out at 55 miles per hour.