Protests Turn Violent As Activists Clash With Police

More than 20 climate protestors have been arrested during clashes with riot police in the heart of Melbourne.

Footage shows scuffles breaking out as police attempted to move on hundreds of demonstrators blocking the entrance of the Melbourne Exhibition and Convention Centre.

Many in the crowd could be heard chanting "we have the right to demonstrate, this is not a police state," and "shame, shame Victoria Police" as they attempted to push back the police line.

Others held signs calling for mining to be "shut down".

Mounted police were called in to protect the building's entrance just after 7 am on Tuesday,  with officers on horseback reportedly galloping at crowds in a bid to move demonstrators on.

Police were also forced to use pepper spray on the unruly group as a number of protestors allegedly pushed and shoved officers while yelling at those trying to get into the building.

More than 20 people were arrested for blocking the wheelchair access to the building, Victoria Police confirmed in a statement.

Victoria Police deploy OC spray on environmental protesters in Melbourne. Image: James Ross via AAP

Two others were detained in relation to animal cruelty offences for allegedly assaulting a police horse.

One officer received minor leg injuries during an arrest and was treated at the scene by paramedics.

Ambulance Victoria confirmed that a police officer and a woman were taken to hospital, both in a stable condition.

The activists are from 23 separate groups including Extinction Rebellion, which ran a week of disruptive climate protests earlier this month.

They're calling for a halt to the International Mining and Resources Conference, a three-day event being attended by more than 7000 experts from across the globe.

Demonstrators booed officials attempting to enter the building ahead of the meeting on Tuesday.

Emma Black, a protest organiser told 10 News First that the protest has been in the works for four months.

"We all came together today because we all have a common enemy. These multinational mining criminals... they tick every box of violations and atrocities".

Image: James Ross AAP

Black confirmed that the aim of the blockade was to shut down the conference and to raise awareness about the "kind of human rights violations and climate catastrophe that these companies have ridden to the planet".

She also confirmed that activists had not communicated the action with police ahead of the blockade.

"We don't think the police have a right to know every strategy and every tactic we're going to use -- that would just be idiotic for us to give them that information so I don't think we've done anything wrong".

While the action was expected to cause chaos on the roads, the Traffic Management Centre confirmed to 10 daily that there were no significant delays during the morning peak hour.

Clarendon St trams could be affected on Tuesday and Wednesday, with commuters urged to check Twitter and the Yarra Trams website for live updates.