A stack of MH370 safety investigation report booklets is pictured at a closed-door meeting with family members in Putrajaya, Malaysia July 30, 2018. REUTERS/Sadiq Asyraf

KUALA LUMPUR (Reuters) - Investigators released a probe report on Monday into the missing Malaysia Airlines jetliner MH370 and said they were unable to determine the cause of one of the world’s greatest aviation mysteries.

“The team is unable to determine the real cause for disappearance of MH370...,” Kok Soo Chon, head of the MH370 safety investigation team, told reporters.

“The answer can only be conclusive if the wreckage is found,” he said when asked of they would ever find out what happened on the plane.

Flight MH370 disappeared on its way from Kuala Lumpur to Beijing on March 8, 2014, with 239 people on board.