The main search and rescue effort has been completed at the site where a China Eastern Airlines Corp. jet nosedived into a hillside last week, killing all 132 passengers and crew. 

More than 49,000 pieces of wreckage were found during the search, Zhang Zhiwen, a senior official of the Guangxi autonomous regional government, said at a briefing Thursday in Wuzhou, near where the Boeing Co. 737-800 NG crashed on March 21. Officials said earlier that DNA matching had been completed and everyone on the aircraft identified. 

President Xi Jinping chaired a meeting of China’s top leadership Thursday, which called for information about the cause of the crash to come in a timely, accurate and transparent manner, according to the official Xinhua News Agency. 

If an accident occurs due to a “failure to implement responsibilities” then “relevant leaders should be held accountable,” state media said citing the Politburo’s seven-member Standing Committee meeting, underscoring the political stakes involved in the investigation.  

Investigators will try to piece together the plane’s final moments from images reviewing trajectory, altitude, the force of impact and air-traffic data. The plane’s two black boxes have already been recovered and sent to Beijing for analysis. 

A preliminary report will be produced within 30 days of the crash, as required by United Nations standards governing the aviation industry, but it won’t include any conclusions as to its cause. A full report is expected within 12 months. 

Flight MU5735 from Kunming was cruising at about 29,000 feet (8,840 meters) and some 100 miles from its destination in Guangzhou, southern China, when it suddenly went into a steep descent. Over the next 1 minute and 35 seconds the plane lost altitude in a near vertical dive, which took it almost to the speed of sound. 

The plane briefly halted its descent for about 10 seconds, and climbed a little, before plummeting into a hillside. 

Some 34,000 rescue workers and staff were involved in the search. Officials said Thursday’s briefing would be the last on the crash to be held in Wuzhou.