Three people were dead and dozens plucked from roofs and marooned cars in dramatic air rescues in northeastern Australia Monday as severe floods swept through two states, inundating thousands of homes.
The bodies of two men swept away by floodwaters were found Monday, one in the Queensland state capital Brisbane and another further north at Gympie, following the earlier discovery of an elderly man's body near the city of Bundaberg.
A pregnant woman and her three-year-old son were rushed to hospital after a large tree fell on them as they were walking Monday morning in Brisbane. They were reported to have head injuries, with the child in a critical condition.
There were dozens of dramatic rescues as rapidly rising waters left people suddenly stranded, including one family who had to zip their infant son into a waterproof bag to be winched to safety by helicopter as floods surrounded their car.
Queensland Premier Campbell Newman said there was an acute emergency unfolding in Bundaberg, home to about 50,000 people 360 kilometres (220 miles) north of Brisbane, with many people scrambling to get out as the river hit a record peak.
Newman said authorities were now in "uncharted territory", with debris-laden floodwaters roaring through the town at such speeds water evacuations were no longer viable and there were fears homes could be ripped from their foundations.
More than 2,000 homes had flooded and "many thousands" of people were affected, he said, with a "significant number" of people expected to be trapped in their homes.
Some 60 patients at the local hospital were being shifted to its upper floors.
"We are at a point where we've never seen floodwaters like this before," Newman told reporters.
"We're very concerned that the velocity of the water and the rise in water levels means that literally houses, particularly in North Bundaberg and maybe other locations, could be swept away. This is a very real prospect."
Fourteen helicopters including two army Black Hawks would fly rescue missions until nightfall and Newman said the government was scrambling to find extra aircraft to boost efforts.
"We've got to pull all stops out to do this before it gets dark," he said.
Thousands of people have evacuated their homes across Queensland with flood warnings for the majority of the state's rivers as ex-tropical cyclone Oswald sweeps into neighbouring New South Wales bringing high winds and heavy rains.
Prime Minister Julia Gillard said the "wild weather had broken a lot of hearts", with some Queensland residents experiencing their third flood in two years, including the devastating 2011 inundation which killed 35 people.
"As this weather moves into New South Wales can I reiterate to everyone, it is very important you keep yourself safe," said Gillard.
"We have seen three fatalities and... we have got grave concerns for a number of others."
Floodwaters were rising in Brisbane, home to some two million people, though Newman said its river was expected to peak some seven metres lower than in 2011, when flooding brought the city to a standstill for several days.
Almost 250,000 homes across Queensland were without power Monday and the triple-zero emergency phone network was down in a number of areas, with mobile phones also out of service.
Rural towns were isolated by floodwaters in neighbouring New South Wales state, where hundreds of millimetres of rain and strong winds were expected in coming hours, including in Sydney.
Cyclones and floods are common in Australia's northeast during the warmer summer months, with a series of huge storms wreaking havoc across Queensland in early 2011, devastating large agricultural districts and key coal mines.