A Malaysia Airlines plane bound for Japan was forced to turn back to Kuala Lumpur due to pressure problems inside the aircraft after being in the air for almost an hour.
A top aviation watchdog official told AFP news agency on Sunday that the plane returned to the Malaysian capital because it was unable to maintain the correct pressure inside the aircraft.
"It was not able to maintain the right pressure differential for the comfort of the passengers," Azharuddin Abdul Rahman, director-general of the Department of Civil Aviation, said. "It is not a major problem."
Malaysia Airlines officials could not be reached by AFP for comment.
The Malaysian publication Star Online reported that the Tokyo-bound flight was 50 minutes into its journey when it was forced to return to the Kuala Lumpur International Airport, after taking off on Sunday at 0250 GMT.
Passengers were subsequently transferred to another plane which departed at 0515 GMT, it said.
The flag carrier, which prior to this year had a good safety record, has been in the spotlight recently.
In the past six months, the airliner was hit with two tragedies -- the disappearance of flight MH370 on March 8, and the shooting down of MH17 on July 17 while flying over rebel-held eastern Ukraine.
The two incidents killed 537 passengers.