WATCH: 3AW reporter Alicia Byrne filmed this video at the protest [25 seconds]
UPDATE: Thousands of protesters have brought the city centre to a standstill as they protest against the closure of Aboriginal communities in Western Australia.
Marchers held placards and shouted "always was, always will be, Aboriginal land" and "stop the genocide".
Frustrated commuters are dealing with peak hour chaos as trams sit idly waiting to get through the crowds.
Earlier, the organiser of the protest told Neil Mitchell they fully intend to "shut down Melbourne" tonight and make life as difficult as possible for commuters.
Organiser Meriki Onus accused the government of committing "genocide".
In April, the Warriors of the Aboriginal Resistance staged a protest starting at Flinders Street that brought the city to a standstill and caused commuter chaos.
When questioned whether the plan was to "shut down the city" she responded "yes".
"12,000 people are coming, we've got a message to say and there's a lot of people concerned at the genocide perpetuated by the Western Australian Government," she said.
But Neil Mitchell dared to ask Ms Onus to define genocide.
"You're saying the current government is engaging in genocide?
"You're throwing around a word like genocide and you don't know what it means.
"You're talking rubbish, can I suggest you buy a dictionary?"
They are expecting as many as 12,000 protesters and will gather at the Town Hall at 4pm, before moving to Flinders Street.
LISTEN: Neil Mitchell takes on protester "talking rubbish"