A United plane that may have caught fire over California made a quick "roller coaster" descent into Ontario International Airport at about 9 a.m., according to the Federal Aviation Administration and a passenger's account.
United flight 1181 turned back to Southern California from its original flight path to Washington Dulles International Airport from Los Angeles International Airport, according to the FAA.
"The flight landed safely after diverting to Ontario, California, due to reports of a burning smell," according to a statement released by United.
All 199 passengers and seven crew members who were on board the Boeing 757 are safe, the airline said. Maintenance crews are working to review the aircraft and "working as quickly as possible to get our customers to Washington, D.C."
A passenger tweeted from the airplane when it landed, describing light smoke in the cabin and a flurry of firefighter activity around the plane once it stopped on the Tarmac.
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"25,000 feet to 0 in 5 minutes. A roller coaster!" said Mitchell Hashimoto, who tweets under the handle @mitchellh. The tweet has now been deleted.
The airplane caught fire mid-flight, saying the landing was "not comfortable," Hashimoto said in another since-deleted tweet.
Another person tweeted that they were being evacuated from the plane in Ontario after smoke was seen on the flight. "This is crazy," said William Mayer, who tweets at @cigarash.
The plane's flight path, posted on a flight-tracking website, shows it circled back to the LA area soon after taking off from LAX , making it no further than about Palm Springs.