Thailand airlifted patients out of Hat Yai in the southern Songkhla province on Wednesday, while flying in emergency equipment like oxygen tanks to treat the wounded, after major floods hit the city. 

Several days of torrential rains have led to flooding in nine Thai provinces and eight states in neighboring Malaysia, displacing around 50,000 people in both countries.

People took refuge on the rooftops and hospitals were flooded in Hat Yai, a commercial hub in southern Thailand, which saw 335 millimeters (roughly 13.2 inches) of rain in a single day, a 300-year record. 

Thailand's military mobilized some 200 boats, 20 helicopters and its only aircraft carrier to help with flood relief and rescue efforts. 

"There have been 33 deaths across seven provinces," Thai government spokesman Siripong Angkasakulkiat said in Bangkok. "Causes of death include being swept away by currents, drowning, electrocution, and landslides."

Aircraft drop supplies to residents, government appeals for boats, jet skis

Provincial authorities said late on Wednesday on social media that the floodwaters were beginning to recede, but that strong currents were hindering rescue efforts. 

Military helicopters dropped equipment to residents gathered on rooftops, while other aircraft flew in key materials like generators, oxygen tanks and drinking water. 

The country's aircraft carrier, Chakri Narubet, set out from its home port on Tuesday to join the relief efforts, the navy said. 

The government also appealed to the public for the donation of useful relief equipment such as boats or Jet Skis. 

The Interior Ministry said that flooding across nine provinces, mainly in the south, had affected more than 980,000 homes or around 2.7 million people. 

Hat Yai's main hospital was inundated, forcing authorities to relocate around 600 patients, 50 of them in intensive care.

The weather system that dumped a total of around 630 millimeters of rain on Hat Yai in the past days has moved away toward the Strait of Malacca and is expected to move towards Indonesia. 

Flooding in eight states in Malaysia

Eight regions of neighboring Malaysia recorded flooding, with forecasters predicting more rain in the coming days. 

The country moved more than 27,000 people to temporary shelthers this week, with one death recroded in Kelantan, one of the worst-hit states in the northeast. 

The country's monsoon season runs from November to March. 

The Foreign Ministry said that it was also monitoring the more severe flooding across the border, with thousands of Malaysian holidaymakers stranded in Thai hotels last week. 

"Most of the affected Malaysians had been staying in multi-story hoteals and have been accounted for," the ministry said in a statement. As of Monday, it said, "more than 6,300 Malaysians have safely crossed the border out of Thailand." 

Edited by Karl Sexton