Passengers on a US flight which made an emergency landing at a military base after a sudden drop in cabin pressure took dramatic pictures of a hole in the aircraft.
Ian Gregor, a Federal Aviation Administration spokesman in Los Angeles, said the cause of the decompression was not immediately known.
He said the pilot of the Southwest Airlines plane "made a rapid, controlled descent from 36,000 feet to 11,000 feet after the incident occurred".
Some passengers aboard the flight from Phoenix, Arizona, to Sacramento, California, said a hole in the cabin caused a rapid descent.
"It dropped pretty quick," said Brenda Reese, who provided mobile phone photographs of the cabin damage in the Boeing 737. The pictures show a panel hanging open in a section above the plane's middle aisle, with a hole of about six feet long.
""The panel's not completely off. It's like ripped down, but you can see completely outside. When you look up through the panel, you can see the sky." Ms Reese said by telephone.
Ms Reese said the plane had just left Phoenix Sky Harbour International Airport when she awoke after hearing a "gunshot-like sound" in the cabin and oxygen masks dropped for passengers and flight attendants.
Dallas, Texas-based Southwest said there were no injuries among the 118 people aboard, but Ms Reese said "there were some people that were passing out because they weren't getting the oxygen". She said one flight attendant's oxygen did not work and that he fell and suffered a bloody nose.
Authorities said the plane landed safely at Yuma Marine Corps Air Station/International Airport at 4.07pm local time on Friday, 150 miles south west of Phoenix and about 40 minutes after take-off from Sky Harbour.
The National Transportation Safety Board later said an "in-flight fuselage rupture" forced the plane to make the emergency landing.