Low tide got a ferry stuck on a mud bank in the Kuala Kedah estuary, causing more than 500 passengers and crew to be stranded.
The local national news agency Bernama says the ferry left Langkawi for Kuala Kedah carrying 545 passengers and eight crew members when it ran aground around 3 pm.
The Malaysian Maritime Enforcement Agency, efforts were being made to remove passengers from the vessel.
MMEA performed a medical evacuation at 5.37pm, according to Kuala Kedah maritime director Noor Azreyanti Ishak, because several passengers were experiencing shortness of breath.
