The Civil Aviation Administration of China (CAAC) said Monday that its investigation into flight MU5735 that crashed a year ago is still in progress, as the case is "very complex and extremely rare."

The Boeing 737-800 aircraft, operated by China Eastern Airlines, crashed into a mountainous area in Tengxian County, Guangxi Zhuang Autonomous Region on March 21, 2022, claiming the lives of all 132 people aboard.

The aviation regulator said the CAAC and relevant departments conducted in-depth, meticulous and rigorous technical investigations into the accident in the past year.

The investigation team will continue to conduct cause analysis and experimental verification work and release relevant information promptly according to the investigation's progress, the regulator said.