Hundreds of people protesting against the treatment of refugees on Manus Island have shut down a major CBD intersection.
A ring of more than 100 police officers have encircled the rally at Bourke Street after protesters marched down Swanston Street on Friday evening chanting "bring them here and end the siege" and waving placards that described Manus Island as "Guantanamo Bay" and "murder".
Others clutched photographs of asylum seekers who have died in detention.
A spokeswoman for VicRoads said the protest has blocked the intersection on Spring Street at Bourke Street and traffic is encouraged to avoid the area.
She said city bound motorists on Nicholson Street trying to get to Flinders Street should turn right onto Victoria Street and use Exhibition Street as an alternative.
The rally was organised by the Refugee Action Collective in solidarity with more than 600 men who have refused to leave the Australian-funded regional processing centre on Manus Island over fears for their safety outside.
"Manus refugees remain strong, and are refusing to be forced from one prison to an even worse one," said Refugee Action Collective spokesman Chris Breen said.
"Immigration Minister Peter Dutton, has tried to brush aside descriptions of his actions as terrorism, but coalition government refuses to guarantee the safety of refugees forced to Lorengau. Threats of violence have been made by someone who appears to be a member of PNG defence forces against the refugees. Such threats are made possible by the actions and policies of the Australian government. The policy of offshore processing is inherently cruel and unstable. The refugees on Manus remain Australia's responsibility and must be brought to Australia."
The United Nations' human rights chief has lashed out at the Turnbull government, expressing "serious concerns" over the welfare, safety and well-being of the men.
The centre was closed on October 31 and Australian contractors and service providers have left the island.
The intersection was open by 9pm.