The Queensland floods have claimed three more lives as the city of Toowoomba was devastated by a wall of water compared to a tsunami.

In an extraordinary turn of events since the unprecedented flooding crisis cut off the city of Rockhampton, flash flooding has sent up to two metres of seething, dirty water coursing down Toowoomba’s streets.

Police confirmed a female pedestrian was one of the three killed by the raging torrents in the city west of the Queensland capital of Brisbane, and up to 20 more are missing.

The floods hit at midday, AEST.

the Australian floods death toll now stands at nine since Rockhampton was first hit in November.

Police and rescue crews are also responding to three pedestrians and two vehicles swept from a roadway at Withcott, in Lockyer Valley, at the foot of the Toowoomba mountain range.

Emergency supplies cut off for Rockhampton

Withcott looks like it’s been hit by “an atomic bomb”, Lockyer Valley mayor Steve Jones said.

Jones said cars had been swept from a local service station into shops.

“There’s petrol pumps taken out and taken half a kilometre down the road. It’s like Cyclone Tracy hit it.”

The town has no power and communications are limited to mobile phones, he said.

Video footage from Toowoomba shows vehicles, some with drivers still trapped inside, being swept away and thrown into the sides of other cars and caught up in trees.

One pedestrian could be seen trying to dodge cars charging along what was once a street.

Deputy Police Commissioner Ian Stewart said lives were under threat.

“We’ve had multiple 000 calls requesting urgent assistance from people caught in vehicles, caught on the street, caught in floodways,” he told reporters.

“This has just evolved. There has been no warning of this event.”

A bridge has also been swept away in the Toowoomba’s south and a building has collapsed on Schofield Street in centre of the city.

Queensland Premier Anna Bligh was in a meeting with flood recovery experts about the deluge in Rockhampton when she was told about the drama unfolding in Toowoomba.

She said a “massive deluge” had hit the city.

“The city has been split through the main centre of town,” she said.

Toowoomba councillor Joe Ramia said he’d never seen anything like the downpour in all his life living in the city.

“I’ve lived here all my life and I’ve seen streets and football fields and ovals and school ovals that are just oceans of water,” he said.

“Cars were floating, they’ve got streets barricaded off, there were wheelie bins floating around. I’ve seen streets in Toowoomba that I never, never thought would carry that much water. It was just horrendous.”

Queensland is now facing floods on three fronts – the cities of Bundaberg and Rockhampton, where peak floodwaters are falling only slightly; southern Queensland centred on Maryborough, where flooding has only just started; and western Queensland, where floodwaters peaked in St

George at the weekend after previously peaking further upstream in Chinchilla and Dalby.

A major concern now is that the ground is so waterlogged the heavy rains are unable to be absorbed and full watercourses are bursting their banks.

The rains have also spread over the New South Wales border, with the Richmond River at Kyogle measured at 4.6m and still rising, while Lismore is among the larger towns in the firing line of the Wilsons River.

The Brunswick River, which runs through Mullumbimby, is also liable to burst its banks, according to the weather bureau.

There was a real threat that homes and businesses in Brisbane could flood in coming days despite critical protection afforded by the Wivenhoe dam west of the city.

Lord Mayor Campbell Newman said the dam was doing its job, protecting the city from a repeat of the 1974 floods which devastated thousands of homes in Brisbane and Ipswich.

But with rain still falling, essential releases continuing from Wivenhoe, and a king tide due on January 21, Mr Newman said residents along the Brisbane River must be ready for flooding.

The council had ordered 30,000 sandbags, which will be filled and available for distribution from council depots.

Bligh said the dam, built after the 1974 floods devastated thousands of Brisbane and Ipswich homes, was seeing “massive inflows” to rival that disaster.

“We are seeing one million megalitres or two Sydney harbours flow into the Wivenhoe catchment every day,” she said.

“Without a doubt the Wivenhoe Dam has already saved Brisbane from a catastrophic flood in the next 48 hours but we have to keep releasing water from it so it can keep doing the job it’s doing.

“The dam will see releases over the next two to three days larger than it has ever seen in its history …”