The state agency that investigates workplace accidents says it was an entire tree — not just a branch — that fell onto a roller coaster's tracks in California, dislodging the front car and keeping nearly two dozen riders stranded about 20 feet in the air for hours.
Peter Melton, a spokesman for the Division of Occupational Safety and Health, said Tuesday that the Ninja coaster at Six Flags Magic Mountain will remain closed until investigators determine exactly what went wrong.
Firefighters and park maintenance workers removed the last of the 22 people stuck on the Ninja coaster about three hours after the accident Monday night.
Two passengers were transported to a local hospital "for precautionary measures," according to a statement sent out late Monday by the theme park.
The ride will be temporarily closed Tuesday for inspection, according to the statement.
The Ninja coaster struck the tree about 5:30 p.m. and stopped, said Michael Pittman, a Los Angeles County Fire Department dispatch supervisor.
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.
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. A few passengers remained on board nearly three hours after the accident. Twenty-two people were on board.
Pittman said four people on the ride received minor injuries, but they and other riders remained on the stalled coaster, stranded 20 to 30 feet in the air, more than an hour after the accident.
The Ninja coaster can hold up to 28 riders.
"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.
Six Flags Magic Mountain is in the Valencia area of Santa Clarita, about 25 miles north of Los Angeles.
The Associated Press was unable to reach Magic Mountain representatives after-hours.
This story has been updated.