Hundreds rescued, evacuated in Australia floods | On camera

Hundreds of people have been rescued and evacuated as floodwaters inundated towns in Australia's New South Wales state on Monday.

The town of Lismore in the state's far north was bracing for its worst flooding on record.

Downtown Lismore was overwhelmed on Monday after days of unrelenting rain, and 15,000 people had been evacuated, officials said.

New South Wales state premier Dominic Perrottet said the flooding was "unprecedented" and warned residents to expect the floods to worsen.

"Many would have seen distressing images of survival and there are many distressing reports, particularly around the Lismore area, of people who are isolated and currently stranded, and I want to make it clear that we are doing everything we can to provide help and support as quickly and as safely as possible," he told reporters in Sydney.

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Rescuers used boats and jet skis in the town's flooded streets to rescue people, while others waded through a flooded bridge.

Meanwhile, parts of Australia's third-most populous city Brisbane were under water on Monday after heavy rain brought record flooding to some east coast areas and killed seven people.

The flooding in Brisbane and its surrounds is the worst since 2011 when the city of 2.6 million people was inundated by what was described as a once-in-a-century event.