Last Updated Jul 8, 2014 12:41 AM EDT
SANTA CLARITA, Calif. -- A roller coaster hit a tree branch at the Six Flags Magic Mountain amusement park Monday evening, dislodging the front car and leaving six people injured, authorities said. Twenty-two people were on board at the time and were left stranded about 20 feet in the air, some for hours, authorities said.
The Ninja coaster struck the branch about 5:30 p.m. and stopped, said Michael Pittman, a Los Angeles County Fire Department dispatch supervisor.
L.A. County Fire Inspector Fred Flores told CBS Los Angeles it was a large pine tree.
Televised news reports showed at least one of the cars that normally are suspended beneath the track dangling at an angle, derailed at the front.
CBS Los Angeles reports that, "A clamp on the number one car connecting the ride to the rail broke off at the impact point. The car could be seen dangling 20-30 feet above ground, held onto the ride by a rear clamp attached to the number two car."
Firefighters and park maintenance workers in harnesses could be seen removing the riders one by one from coaster cars. Others waited patiently, some talking with each other and others resting with their eyes occasionally closed.
Many riders were stranded nearly three hours, says CBS Los Angeles, adding that all had been rescued by approximately 8:35 p.m. local time. The Ninja coaster can hold up to 28 riders.
Sgt. Jeff Curran of the L.A. County Sheriff's office out of Santa Clarita told CBS News six people were injured and two of them were taken to a hospital with non life-threatening injuries.
Magic Mountain said in a statement that the ride "will remain closed until a thorough inspection of the area is complete."
"As you shoot down the snake-like steel track, you'll grip the hillsides and blast through the trees swiftly, slicing through the landscape. Ninja pivots with precision as you narrowly miss tagging land and water, whipping around at 55 miles per hour," according to the amusement park's website. CBS Los Angeles says riders hang from the cars and are swung 90 degrees in each direction.
Six Flags Magic Mountain is in the Valencia area of Santa Clarita, about 25 miles north of Los Angeles.