The airline confirmed the aircraft returned to Shanghai "due to some mechanical anomaly."
Passengers later confirmed there were three loud bangs and a listener monitoring air band frequencies reported the crew indicated an engine failure on climb out.
The flight was cancelled, the passengers were rebooked onto flight MH-387 the following day (Airbus A330-300 registration 9M-MTA) and reached Kuala Lumpur with a delay of 24 hours.
The Boeing aircraft is still on the ground in Shanghai, and has not returned to service.
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