MELBOURNE - Australia's most populous state of New South Wales reported on Sunday 141 locally acquired cases of COVID-19, down from 163 a day earlier, but there are fears of a wave of new infections after thousands of people joined an anti-lockdown protest.

"In relation to yesterday's protests, can I say how absolutely disgusted I was. It broke my heart," state premier Gladys Berejiklian told reporters.

The outbreak is largely being driven by the highly contagious Delta variant of the virus.

Of the new cases, at least 38 cases had spent time in the community while infectious, state health authorities said.

That figure has stayed stubbornly high even after four weeks of lockdown in Sydney, now expected to be extended beyond July 30.

The state reported two deaths overnight, including a woman in her 30s with no pre-existing conditions.

Despite its struggle with spikes of infections, Australia has managed to keep its epidemic largely under control with a total of about 32,600 cases and 918 deaths.

(Reporting by Sonali Paul Editing by Robert Birsel) ((Sonali.Paul@thomsonreuters.com; +61 407 119 523;))