According to a report relating to the crash of a China Eastern Airlines jet in March, it is now believed that the crash was caused due to an intentional nose dive.
The China Eastern Airlines Boeing 737-800 crashed into the mountains of Guangxi on 21 March during a flight from Kunming to Guangzhou.
All those on board were killed in the crash - 123 passengers and nine crew members.
The Wall Street Journal reported on Tuesday that flight data from one of the plane's black boxes indicated that someone in the cockpit deliberately crashed the jet.
The report cited people familiar with a preliminary assessment done by US officials, adding that no evidence had been found so far of the plane getting into any technical difficulties during the flight.
It is still unclear whether the hypothesis drawn from the investigation is that of a pilot acting alone, a struggle, or a passenger breaking into the cockpit.
China Eastern Airlines stated that a cockpit intrusion was not plausible, with authorities saying that no emergency code was sent from the plane before the crash.
During the rapid descent of the jet, it was reported that the pilots never responded to repeated calls from air traffic controllers and nearby planes.
The US National Transportation Safety Board and Boeing both refused to comment on the report, however, China's Civil Aviation Administration said in April that internet rumours of a deliberate crash had "gravely misled the public" and "interfered with the accident investigation work."
The Wall Street Journal cited the Chinese airline as saying that no evidence had emerged that could determine whether or not there were any problems with the aircraft.
The 737-800 has been in service since 1997 and holds a strong safety record, it is a predecessor to Boeing's 737 MAX.
The 737-800 does not have the systems linked to the 737 MAX crashes in 2018 and 2019, which left hundreds of people dead and led to the model being grounded all over the world.
Following the China Eastern crash in March, the airline grounded all of its 737-800s but they all resumed flight again in April - a move that was interpreted as ruling out any safety concerns.
Chinese officials have said that a final report on the crash could take more than two years to complete.