Emergency workers in China have found on Wednesday a black box from the Eastern Airlines plane that crashed on Monday in Guangxi Province with 132 passengers on board, according to the aviation regulator.

Flight MU5735 was heading from the southwestern city of Kunming to Guangzhou on the coast when the Boeing 737-800 suddenly plummeted quickly, losing more than 8,800 meters of altitude in a matter of minutes.

The reason for the crash has not been determined yet. The jet appears to have mostly been destroyed upon impact, but some debris and human remains have been found.

"An initial inspection showed that the exterior of the recorder has been severely damaged, but the storage units, while also damaged to some extent, are relatively complete," an official from the Civil Aviation Administration of China (CAAC) said.

The black box, which is one of two that were on board the plane, was taken to an institute in Beijing. The extent of the damage will determine how much time it would take to be decoded, Zhu said.

Monday's weather did not pose any danger to the airplane and air controllers had contacted it after take-off and before its fast descent, according to the head of aircraft investigation at CAAC, Mao Yanfeng.

The aircraft did not respond to several calls while descending, Chinese authorities said, adding that it met airworthiness standards before taking off and the 3 pilots who were on board, were all healthy.

Consequently, Chinese authorities invited the US National Transportation Safety Board to be involved in the investigation of the crash.