Hundreds have been arrested after violent clashes between anti-lockdown protesters and police in Australia's two largest cities as the country records its sharpest rise in daily Covid-19 cases since the pandemic began, reports AFP.

Sydney's state of New South Wales (NSW) has posted 825 infections — a record for the entire country — a day after authorities extended the city's lockdown until at least September to try to head off the Delta variant.

Meanwhile, an outbreak in Melbourne's state of Victoria also prompted stay-at-home orders to be extended across the entire state.

But Melbourne's public health orders didn't deter thousands from venting anger in a march against the lockdown rules, with police using pepper spray in violent clashes with protesters. Seven officers were injured and more than 200 people were arrested in the “violent and unlawful” protest, Victoria Police said in a statement.

In Sydney, more than 1,500 policemen flooded the city, setting up roadblocks and making dozens of arrests as around 250 gathered there, NSW Police said.