SYDNEY — Australian police are investigating after a senator was allegedly thrown to the ground at a protest outside parliament in Canberra.

Senator Lidia Thorpe was attempting to confront British activist Kellie-Jay Keen-Minshull, who was holding an event outside the building.

Footage showed Ms Thorpe approaching Ms Keen-Minshull before appearing to be pulled to the ground by police.

Police say their professional standards unit is now investigating.

Ms Keen-Minshull - who describes herself as a women's rights activist, but is also widely known for her opposition to transgender rights - was holding a "Let Women Speak" rally attended by a small number of supporters. It had attracted a larger counter-protest by pro-LGBT activists.

As she spoke, Ms Thorpe was seen approaching the microphone area shouting "you're not welcome here" before being pushed back by a man in a suit, and then apparently pulled to the ground by police.

Police attempted to get her back on her feet but Ms Thorpe shouted "let me go", before breaking free and crawling away across the wet grass, and then standing up and walking off.

Speaking to reporters after the incident, Indigenous Australian Ms Thorpe said: "We do not tolerate this kind of filth being on Ngunnawal-Ngarigo country," referring to Ms Keen-Minshull's group's presence on Aboriginal land.

"They are racist. They are homophobic. They are destroying people's lives. This country should be ashamed that they even let people like this into this country."

Ms Thorpe later told the Guardian she had been "pulverized" by police, and Indigenous Affairs Minister Linda Burney described the incident as "disturbing and concerning".

"My concern was for, is for, Lidia... I think the fact that it has been referred to the professional standards unit is absolutely appropriate," she told the Australian Broadcasting Corporation.

In a statement, police said "interactions" between the police and protesters at the event would be reviewed, and that no further comment would be made with the matter under investigation.

Last weekend, Ms Keen-Minshull's rally in Melbourne sparked outrage after a neo-Nazi group appeared outside Victoria's state parliament in apparent support.

She has denied any links to the group, describing them to The Australian newspaper as "sad and pathetic".

Her Canberra event attracted the right-wing populist One Nation Party senators Pauline Hanson and Malcolm Roberts, but no politicians from either major party attended.

Lidia Thorpe was elected to parliament as a member of the Greens last year, but left the party in February over its support for the Indigenous Voice to Parliament, which she opposes in favor of the "Black Sovereignty" movement.

Earlier this month, she alleged she had been the victim of sexual harassment and assault at Canberra's Parliament House during her time as a Green.

Ms Thorpe has staged attention-grabbing protests, which include lying down in front of a float at this year's Sydney's Gay Pride parade to oppose police taking part.

In 2022, she was also made to repeat her oath of office after adding in a reference to Australia's head of state, the late Queen, being a "colonizer". — BBC