Flash floods swept through the Australian city of Toowoomba Monday, killing at least eight people, trapping others in cars and leaving some clinging to trees as relentless rains brought more misery to a region battling its worst flooding in decades.

Seventy-two people were said to be missing.

The raging torrent of muddy water picked up cars and tossed them like toys, carried away furniture as it washed through stores and prompted scores of emergency calls as it swamped the city of about 90,000 in Queensland state in the northeast.

At least eight people were killed, including a female pedestrian, said Tom Dawson, assistant commissioner of the Queensland fire and rescue service.

Officials urged residents of low-lying communities downstream from Toowoomba to move immediately to higher ground because more flash floods were possible.

Video taken in Toowoomba shows a man clutching a tree as the gushing water sweeps down a street, pushing vehicles off the road and into each other and flinging a van into trees. A small sedan is tossed about in murky brown rapids.

"We've had multiple calls requesting urgent assistance from people caught in vehicles, caught on the street, caught in flood ways," said Ian Stewart, the Queensland deputy police commissioner, adding that the flash flood happened with no warning.

It was the latest drama for water-weary Queensland, which has been devastated by weeks of pounding rains and overflowing rivers. Fourteen people have died since late November, and about 200,000 have been affected by the floods.

Roads and rail lines have been cut, Queensland's big-exporting coal mine industry has virtually shut down, and cattle ranching and farming across a large part of the state are at a standstill.

Dawson said his group recorded 90 emergency calls from people in conditions that were considered to be life-threatening. Several people were rescued, and officials were still struggling to respond to all of the calls.

Cars washed away

The waters disappeared almost as fast as they arrived, leaving debris strewn throughout downtown Toowoomba and — in one place — cars piled atop one another.

People survey the damage after a flash flood tossed vehicles down a street in Toowoomba, Australia, on Monday. (ABC/Associated Press)

Toowoomba resident Sarah Gordon said she saw floodwaters wash away at least 15 cars.

"A lot of cars got swept down the road … right down the creek," she said. "A few people were trapped, but they luckily got out."

The water also gushed into city businesses.

"The water was lapping at our office door and was just leaking through," said Emily Hart, who works in a real estate office. "It all happened within a matter of an hour. It was a massive amount of water."

Muddy waters also flowed through the main street in the city of Gympie, one of more than 40 Queensland communities to be drenched by overflowing rivers. Gympie residents were frantically sandbagging buildings, but about a dozen businesses were inundated by Monday and dozens more were at risk as the Mary River burst its banks and kept rising.

The flooding in Gympie, home to 16,000 people, was not as bad as that elsewhere in recent weeks, when entire towns were submerged beneath an inland sea larger than British Columbia.

But it was a sign the ground has little capacity left to soak up any more moisture, so any new rain is likely to make matters worse, officials said.

Queensland officials have said the price of rebuilding homes, businesses and infrastructure, coupled with economic losses, could be as high as $5 billion.

Rising water threatens homes

Some areas of Queensland have 343 millimetres of rain in 24 hours, the Bureau of Meteorology said Monday.

Emergency workers rescue a man forced to cling to a tree on a flooded street in Toowoomba during a flash flood. (ABC/Associated Press)

Residents of Dalby, a town west of Brisbane, were evacuated as rising waters threatened to inundate homes that had just begun drying out after another round of flooding two weeks ago.

Dalby Mayor Ray Brown said the town has been cut in half by the swollen Myall Creek, which also overflowed Dec. 27, leaving 100 homes awash in murky water.

Heavy rains were also leaving low-lying communities along the Brisbane River, which flows through the state capital of Brisbane, vulnerable to flash flooding, the Bureau of Meteorology warned. Officials have offered residents sandbags and suggested they have emergency kits ready.

People in some affected communities have returned home and begun mopping up sludge left behind by the floods, while others — including residents of Rockhampton, home to 75,000 people — are still waiting for floodwaters to recede to start the cleanup.