The death toll from the worst floods in decades in southern Thailand and northern Malaysia climbed to at least 12 on Saturday, authorities said, as tens of thousands of people were evacuated due to rising water levels in the past three days.

Floods are common on the east coast of peninsular Malaysia during the monsoon period between October and March, but this week's torrential rain has led to the mass evacuations, mostly in the northeastern state of Kelantan that borders Thailand.