At least 16 other people were injured, the Hospital Authority said.

The Hong Kong Observatory had issued a 'black rainstorm warning' at 6.40am yesterday, the highest level of alert, urging people to stay indoors and employers not to expect staff to report for work.

The 'black' warning means 70mm of rain was expected to fall in just one hour.

Nearly 30cm of rain fell yesterday morning, according to the Observatory, which also recorded winds of up to 70kmh.

It cancelled all severe-weather alerts later yesterday but maintained thunderstorm and landslip warnings.

The bodies of a man and a woman were found in the rubble of a suburban hut yesterday evening, about 12 hours after the storm caused the dwelling to collapse, police spokesman Anne Lam said.

Four other people, including two children, had escaped earlier from the hut, she added.

Fire department district commander Tam Yiu Kei said a massive concrete slab that had fallen on the hut as well as the threat of further landslides had impeded rescue efforts.

'The heavy rainfall has loosened the mud. There's a chance of further landslides. It makes the operation more difficult,' he said.

Floods disrupted traffic at Hong Kong International Airport on Lantau Island, one of the worst-hit spots, an Airport Authority spokesman said.

More than 345 flights - including at least three flights to and from Singapore - were delayed and six were cancelled, according to the airport authorities and airline officials.

'SQ857, a Boeing 777-200 aircraft, carrying 268 passengers, was delayed in Hong Kong for slightly over three hours due to bad weather,' an SIA spokesman said, referring to a Singapore-bound flight.

A highway linking Kowloon on the mainland to the airport was inundated with muddy water.

The storm, fuelled by a low-pressure system over the South China Sea, caused 79 landslides and flooded 539 areas across Hong Kong, government spokesman Suzanne Lee said.

'This is the heaviest rain I have seen in years,' said Mr Edmund Kwan, an office worker, who was waiting for his girlfriend at the Sheung Wan MTR station in the western district.

Shopkeepers stacked sandbags in an effort to keep out the flood waters.

Schools and courts were closed, the government said in a statement.

Many tourist spots, including the Wetland Park and Ngong Ping 360 cable cars, were shut down temporarily. Hong Kong Disneyland was reopened for limited operations after the Black Rainstorm Warning signal was cancelled.

Hong Kong is regularly hit by severe rain and even typhoons between April and September.

In neighbouring Guangdong, three students were swept away by floods and thousands of people were relocated as rainstorms battered the province over the last two days.

AP, AFP