Rescue crews look for survivors in heavy forest area where Chinese flight MU5735 crashed

March 21 (UPI) -- Dozens of forest firefighters on Monday were dispatched to the scene of a crashed Boeing 737 that went down in China carrying more than 130 people.

Some 150 members of the Yunnan Forest Fire Brigade rushed to the mountainous crash site in Guangxi province and were expected to arrive late Monday to begin a search for survivors, state media reported.

The China Eastern Airlines flight MU5735 was headed from Kunming to Guangzhou when it crashed. It had 123 passengers and nine crew.

Investigators said the plane lost contact near the city of Wuzhou and went down in a heavily forested area. Fire was later seen at the crash site.

It wasn't immediately known how many people were killed or injured, or if there were survivors.

Chinese President Xi Jinping was shocked to hear about the crash and ordered an "all-out search and rescue," state-run Xinhua reported.

The crash is the latest involving a Boeing 737 in recent years. Two Boeing 737 Max aircraft crashed in Indonesia and Ethiopia in 2018 and 2019 and forced Boeing to ground the fleet worldwide. The plane maker ultimately found a problem with the 737 Max's automated flight software.

The last major crash involving a Boeing 737-800 occurred on August 8, 2020, when this Air India Express flight ran off the runway at Calicut International Airport in Kozhikode, India. Twenty-one people died. File Photo by Prakash Elamakkara/EPA-EFE

Monday's crash in China, however, involved a Boeing 737-800 model, not a Max. The 737-800, also known as the 737 NG, has a sterling safety record and is considered one of the safest planes in commercial aviation.

"The 737 NG has been in operation for 25 years and has an excellent safety record," Paul Hayes, director of air safety and insurance at Cirium, said, according to Bloomberg. "I'm not going to speculate on what happened but ... something seems to have happened abruptly and the plane nose-dived from cruising altitude."

China Eastern Airlines said after the crash Sunday that it would ground its 737-800 fleet pending an investigation.

Before Monday, the last major crash of a 737-800 plane occurred in August 2020 when a flight slid off the runway in India and killed almost two dozen people. Investigators later blamed the crash on the pilot.