GUANGZHOU, March 21 (Reuters) - A China Eastern Airlines (600115.SS) Boeing 737-800 with 132 people on board crashed in mountains in southern China on Monday after a sudden plunge from cruising altitude at about the time when it would normally start to descend ahead of its landing.
Media said there were no signs of survivors on the domestic flight.
The airline said it deeply mourned the passengers and crew, without specifying how many people had been killed on the jet, an earlier model to the 737 MAX with a strong safety record.
Boeing (BA.N) said it was ready to assist China Eastern and was in contact with U.S. transportation safety regulators over the incident.
Chinese media carried brief highway video footage from a vehicle's dashcam apparently showing a jet diving to the ground behind trees at an angle of about 35 degrees off vertical. Reuters could not immediately verify the footage.
Flight MU5735 was en route from the southwestern city of Kunming, capital of Yunnan province, to Guangzhou, capital of Guangdong, bordering Hong Kong, when it crashed.
China Eastern said the cause of the crash was under investigation. Such accidents typically involve multiple factors and experts warned it was far too early to draw any conclusions on the potential causes, especially in light of the scarce information available.
Investigators will be scouring the wreckage and flight recorders for factors that could have caused the plane to plummet vertically and slam into the mountains at high speed.
The airline said it had sent a working group to the site. There were no foreigners on the flight, Chinese state television reported, citing China Eastern.
The aircraft, with 123 passengers and nine crew on board, lost contact over the city of Wuzhou, China's Civil Aviation Administration of China (CAAC) and the airline said.
The flight left Kunming at 1:11 p.m. (0511 GMT), FlightRadar24 data showed, and had been due to land in Guangzhou at 3:05 p.m. (0705 GMT).
The plane, which the flight tracking service said was six years old, had been cruising at 29,100 feet at 0620 GMT. The same flight number a day earlier began a normal gradual descent from the same altitude, also at 0620 GMT, and landed safely in Guangzhou, according to Flightradar24.
The flight that crashed instead began a rapid descent to 7,425 feet before recovering briefly to 8,600 feet and then descended rapidly again, FlightRadar24 data showed. The last tracked altitude was 3,225 feet above sea level.
Media cited a rescue official as saying the plane had disintegrated and caused a fire destroying bamboo trees. The People's Daily quoted a provincial firefighting department official as saying there was no sign of life among the debris.
State media showed a piece of the plane on a scarred, earthen hillside. There was no sign of a fire or personal belongings.
