Thousands walk for refugees in Melbourne

Holding banners high and chanting loudly, more than 5000 protesters came together at the State Library of Victoria to rally against Australia's immigration detention centres.

Protest songs were played to the crowd that filled the front lawn of the library as speakers told the crowd of Australia's "both brutal and unsustainable" offshore detention system.

Now is the time for people to increase their pressure on the government to close down Nauru and Manus Island, Victorian Women's Trust's Mary Crooks told the crowd.

"To do nothing is a tacit endorsement," she said.

"This is why gatherings like this are important, to show our solidarity."

She described the community's disdain for the government's current policy as obvious, citing the huge crowd and the types of people who attended.

"We've got politicians, churches, schools and the community," she said.

The crowd then took to the streets, walking through Melbourne to the Queen Victoria Gardens chanting "say it loud, say it clear, refugees are welcome here."

Similar rallies were held in most Australian capital cities, and 19 others throughout the world.

Despite advertising that former child detainee at Nauru, Mohammad Baqiri would speak, he didn't take to the stage before the walk began.