BEIJING (REUTERS) - The cause of the crash of the China Eastern Airlines jet last week must be determined as soon as possible, state media said on Thursday (March 31), following a meeting of China’s highest decision-making body helmed by President Xi Jinping.

Information about the crash on March 21, which killed all 132 people onboard, must be released in an open, timely and transparent manner, state media said in a report on the meeting of the seven-person Standing Committee of the Communist Party’s politburo, China’s top leadership.

A nationwide safety inspection should also be launched to prevent as much as possible the occurrence of safety accidents, state media said.

If accidents do happen due to negligence, not only will the personnel in charge be punished, the relevant top officials will also be investigated, state media said.

Earlier on Thursday, an aviation official said China has completed the main search and rescue work at site of a China Eastern Airlines crash last week and plans to complete a preliminary report within 30 days of the event.

A final report into the crash of the Boeing 737-800 will be completed and made public after the investigation is concluded, Civil Aviation Administration of China (CAAC) safety head Zhu Tao told reporters.

Citing the Standing Committee meeting, state media said all relevant parties investigating the crash are to gather experts to comprehensively analyse the aircraft’s flight data and other evidence, and find out the cause and nature of the crash "as soon as possible".

The plane crashed into a mountainside in southern China on March 21, killing all 132 people onboard.

Under international rules, a 30-day report must be lodged with UN aviation agency ICAO but it does not need to be public.

A final report is due within a year of the crash, though sometimes it can take longer.

Mr Zhu said authorities have done preliminary analyses of the crash, such as predicting the possible trajectory, position and impact force of the airplane when it hit the ground and reading data from air traffic control radar systems.  

CAAC investigators are also working to decode the data from both the black boxes, he added.  

Investigators from the US National Transportation Safety Board are set to travel to China to support the CAAC’s investigation into mainland China’s deadliest aviation disaster in 28 years.  

Over 40,000 pieces of aircraft wreckage and debris have been found and a majority of the pieces have been transported to a hangar, Mr Zhu said.