Victorian Greens senator Lidia Thorpe is demanding an explanation from police after a violent clash occurred with protesters attempting to stop immigration detainees in Melbourne from being transferred to Christmas Island.
Senator Thorpe was among the dozens of refugee advocates who attended Melbourne Immigration Transit Accommodation (MITA) on Tuesday as they faced off with police to prevent the transfer.
Advocates say 12 detainees from MITA were told without notice that they would be transferred from the facility in the Melbourne suburb of Broadmeadows to Christmas Island.
The Department of Home Affairs has not released any details publicly about the movement of detainees.
SBS News understands three detainees have been directed back to MITA after a scuffle with police on the bus.
A spokesperson for Australian Border Force told SBS News the group of people being transferred to Christmas Island consisted of "detainees whose visas have been cancelled due to being a risk to the community".
"[This] includes those convicted of serious crimes relating to assault, illicit drugs, robbery, domestic violence and other offences," the ABF said in a statement.
The ABF said detainees are transferred between immigration detention facilities "to balance the detainee population and security risk".

Protesters gather in front of a bus carrying MITA detainees that advocates say are being transferred to Christmas Island. Source: Supplied / Ian Currie
She said officers on the frontline "stood aside" as others acted like "they were there to hurt people".
"I witnessed these machines, robots with no heart come through while these officers stood aside, and they were there to hurt people. They were there to intimidate people, to cause terror in people's lives," Senator Thorpe said.
Dane Deleon was one of the protesters, who says she was pushed, kicked and pepper-sprayed by the police after she tried to stop the bus from leaving the compound.
"I think eventually my wounds will heal and the stinging will stop but the government's torture will continue to kill until people resist. If there were more people there, we would have stopped the transfer," the community manager told SBS News.

Protesters being pepper-sprayed by Victoria Police officers outside Melbourne Immigration Transit Accommodation (MITA ) in Broadmeadows, Victoria on 3 May 2022. Credit: Ian Currie
She said the number of police responding to the protest and their actions towards the demonstrators was "over the top".
Senator Thorpe accused some of the police of having "no regard for human life".
"That's the worst I've seen, being a protester all my life, these men ... and women ... that just had no regard," she said.
"They're obviously trained to have no regard for human life, and that's very scary for our country".
Senator Thorpe said there needed to be greater oversight available to investigate the conduct of police officers and immigration detention centres where she said "people are being tortured, right under our noses".
"We need independent oversight of police behaviour in this country because they get away with murder," she said.
Senator Thorpe said she and her Greens senate colleagues Nick McKim and Janet Rice would be working together to demand answers about the welfare of the people transferred to Christmas Island, as well as those still detained at MITA.
"We need to know if they're okay, we need to know who else is left in there," Senator Thorpe said.
"We want to know how many people seeking asylum are actually in there, and what are the plans for them?
"We want to know how many people on 501s (visas) are in there."

Protesters scuffle with Victoria Police officers at the Melbourne Immigration Transit Centre in Broadmeadows, Melbourne, 3 May 2022. Source: AAP / JAMES ROSS/AAPIMAGE
He said pepper spray was used "after a small number of protesters failed to comply with lawful directions".
"These people were treated by paramedics at the scene," he said.
Senior Constable Bail said a 24-year-old woman from O'Connor in the ACT was arrested after gluing herself to a vehicle and will appear in court at a later date.
SBS News contacted the Department of Home Affairs for comment.