Recovery crews searched in light rain for a second black box from a China Eastern Airlines plane that plunged into a mountainside with 132 people on board.
A first black box found on Wednesday was the cockpit voice recorder based on an early assessment, a Civil Aviation Administration of China (CAAC) official told reporters. The recording material appeared to have survived the impact in relatively good shape, and was being sent to Beijing for analysis, the official said.
The cockpit voice recorder would provide investigators with details of the communications between the flight's three pilots, which is one more than is normally required on board a Boeing BA.N 737-800 plane.
Flight MU5735 was en route from the southwestern city of Kunming to Guangzhou on the coast on Monday when the plane suddenly plunged from cruising altitude at about the time when it should have started its descent before landing.
According to flight tracking website FlightRadar24, the plane briefly appeared to pull out of its nosedive, before plunging again into a heavily forested slope in the mountainous Guangxi region of southern China.
Chinese authorities said the pilots did not respond to repeated calls from air traffic controllers during the rapid descent.
It is too early to determine the cause of the crash, which experts say are usually the result of a combination of factors. No survivors have been found.
The flight's captain, hired in January 2018, had 6,709 hours flying experience, while the first and second officers had 31,769 hours and 556 hours, respectively, a China Eastern official said on Wednesday. One co-pilot was an observer to build up experience, the airline said, without disclosing the names of the pilots.
Mist and low lying clouds hovered over the small, tree-covered hills in the mainly rural area surrounding the crash site on Thursday.
Drones were readied for deployment to survey the core area of the crash site and capture images to be assessed by experts, state media said. Other drones that can be airborne for more than 12 hours will be deployed to provide night-time light.
Roads leading to the site remained closed off to all but villagers and those allowed entry by police and officials manning makeshift checkpoints.
A line roughly 1 km-long of rescue vehicles, police cars, military trucks, specialist vehicles, buses and other cars were seen parked on the hard shoulder of a highway next to Molang village, which lies close to the crash site.
CGTN footage showed that the recovery crews consisted of militia members, paramilitary police officers, police officers and firefighters.
The crash investigation is being led by China but the United States was invited to take part because the plane was designed and manufactured there.
The US National Transportation Safety Board said on Wednesday it had not yet determined if investigators would travel to China in light of strict visa and quarantine requirements.