More than 50 people have been charged and 250 fined after thousands of protesters marched through the CBDs of Sydney and Melbourne on Saturday, demanding an end to lockdowns.

Images showed a police horse being punched, mounted police being pelted with pot plants and one journalist being robbed of his phone.

Commissioner Mick Fuller said he was aware of talk online about another event planned for this weekend and issued a blunt warning.

"We will take the ground very early. You will be arrested," he said on Monday.

"The community has spoken about that behaviour. The premier has spoken about that behaviour and it won't be tolerated again."

Mr Fuller described the organisers as "anarchists" who, unlike Black Lives Matter protesters who took to the streets in June last year, did not formally register their rally.

"There are no organisers that we can take to the Supreme Court to stop the protests happening which means they're a bunch of anarchists," he said.

Two men accused of striking police horses are among 57 people charged over the Sydney protest and nearly 200 have been fined.

Joseph Mekhael, a 37-year-old conspiracy theorist who makes false claims that coronavirus is a scam and vaccines are murdering people, is now facing four charges of failing to comply with COVID-19 directions after also leading protests in January.

The Merrylands man was bailed on Sunday on conditions that effectively impose home detention.

Crime Stoppers NSW has received more than 10,000 tips, helping police identify more than 200 people who attended and a strike force is analysing footage from social media, CCTV and police-worn body cameras to identify the culprits.

Members of the public are being asked to upload any videos or photos of the protest to Crime Stoppers to track down more participants.

Meanwhile, in Melbourne, police are reviewing hundreds of hours of footage to add to their six arrests and 73 fines already issued.

"Your faces are on the front page of our major newspapers. Your faces are on social media. Your faces are being published, wide and far," Victoria Police Assistant Commissioner Luke Cornelius said.

Their investigation will include the alleged assault of a mounted officer hurt by a flying bollard.

Victorian Premier Daniel Andrews described protesters as "selfish" but was reasonably confident it would not become a super-spreader event, given the state's 11 new cases on Sunday had all been linked and were in isolation.

NSW Premier Gladys Berejiklian said she was disgusted and heartbroken by those who had shown "utter contempt for their fellow citizens".

Meanwhile, federal government MP George Christensen on Monday shared his speech from his local "freedom" rally on Saturday in which he said the "fake news media streams fear porn into our homes every day".

"We should not comply (with restrictions) because, at some point in this fight, civil disobedience is going to have to be done,' he told a rally in Mackay.

Deputy Prime Minister Barnaby Joyce defended his Nationals colleague's right to make the comments while saying he did not agree with the backbencher's views.

Australian Associated Press