China's aviation authority says it's still investigating the cause of last month's plane crash in Guangxi region. All 132 people onboard a China Eastern Airlines jetliner were killed when it plunged to the ground on March 21st. At a press briefing on Monday, the Civil Aviation Administration of China said it was investigating major risks and hidden hazards in the industry to prevent more air accidents. It said it was vital that more emphasis is placed on assessing the psychological status of air crews.