"Threats and intimidation has no place in Australia," the prime minister told reporters in Sydney on Thursday.

"We are a civil peaceful society and when we have disagreements we do not deal with them with violence."

There was no tolerance for violence in Australia regardless of how frustrated people were with governments during the pandemic, Mr Morrison said.

An alleged far-right extremist will face court next week on incitement-related offences.

Home Affairs Minister Karen Andrews said the events leading up to the arrest were "very concerning".

All threats were taken seriously by police and intelligence organisations after the man also allegedly encouraged Victorian protesters to bring guns to a rally.

Victoria Police are investigating a number of recent incidents involving threats directed at members of parliament, as well as the infiltration of anti-lockdown and anti-vaccination protests by far-right extremist groups.

Ms Andrews said the biggest threat to Australia was from lone-wolf actors planning terrorist attacks.

"There are people out there that want to do Australia harm," she told Sky News.

MPs from all sides of politics have revealed threats against them and their families as they remain on high alert a month after the fatal stabbing of a British politician.

Federal Labor frontbencher Tony Burke denounced the violent imagery at protests in Melbourne this week when demonstrators chanted "Kill Dan Andrews" and "Hang Dan Andrews" alongside makeshift wooden gallows outside parliament.

"I've had protests over the years, not with gallows, but with a coffin used on me," he told Sky News.

"When those sorts of protests occur, they are completely out of line and need to be just unequivocally condemned."

Independent senator Jacqui Lambie described as "absolutely frightening" some of the actions at the protests.

"It doesn't matter what you think of Daniel Andrews, it doesn't matter what you think of me, we are still human beings and we have families in our homes," she said.

Australian Associated Press