A climate protester has been taken to hospital and up to 50 others arrested after violent clashes with police outside a mining conference in Melbourne on Tuesday.

About 250 protesters linked to numerous groups were met by 300 police, including at least eight mounted on horses, outside the conference venue about 6am on Tuesday.

There were tense scenes as police used capsicum spray on some protesters, and employed horses to force demonstrators away from the entrance to the Melbourne Exhibition and Convention Centre.

Officers were seen placing people in headlocks and pushing them to the ground. Footage showed one woman being pulled by her hair.

One of the protesters, 23-year-old Camila Serra, was taken to The Alfred hospital in a stable condition – reportedly with a broken leg.

A protester, Paul, said Ms Serra, who is from Chile, was injured when a police horse backed onto her.

“I was standing beside her, one of the police officers had sprayed me, then threw her back away from me, and then the horse reared up and stepped on both of her legs,” he told the ABC.

Protest spokeswoman Emma Black said police had acted aggressively and “thrown” people to the ground without reason.

“Police have been incredibly aggressive but that isn’t unexpected. There’s a lack of communication on their side,” she said.

“I, for instance, have been hit by a baton.”

Ms Black said the activists would continue to disrupt the conference despite the violence.

Police said four officers were injured while making arrests.

Victoria Police Acting Commander Tim Tully defended police behaviour, saying they had acted according to training they had received.

“We have shown a hell a lot of discretion and a lot of tolerance,” he said.

“We have situations where people have been able to engage in passive and peaceful protests. However, when we have requested protesters to move on from areas [they have not].

“Actions have been more than justified.”

More than 7000 delegates from nearly 100 countries are expected to attend the three-day conference, which started on Tuesday.

Among them is Pioneer Resources chairman Craig McGown, who was seen to have a bottle of water poured over him by a protester. He was pushed and during his approach to the conference had a woman shouting “shame” at him.

“I’m just very confused by people having too much time off,” Mr McGown said.

“I’m just in attendance at the conference because my company is involved in major projects that can help the country move forward.”

Tuesday’s clashes erupted as activists faced off against police, who said they were forced to arrest 47 people who were blocking the building’s disabled and wheelchair access and would not move on.

Two people were also arrested for animal cruelty after assaulting a police horse.

“Most of the people arrested have been released with summary offences”, Rohan, a legal guide from the protest, said.

Ms Black said earlier on Tuesday the protest was not to be confused with the Extinction Rebellion movement, which shut down major city streets earlier this month.

Getting nasty here with climate protesters and police clashing outside Jeff’s shed. Mounted officers now trying to split up the pack. pic.twitter.com/ngYwfYSDlR — Nathan Templeton (@nathantemp7) October 28, 2019

“We’re not trying to disrupt motorists or commuters today, we’re simply blockading the convention and exhibition centre here in Southbank,” Ms Black told Channel Seven’s Sunrise as the protest heated up about 7.30am on Monday.

“Our main enemy is the mining executives and investors that are coming here to plot how to further destroy the planet.”

The International Mining and Resources Conference is Australia’s largest annual industry event and attracts delegates from the resources, investing and technology sectors.

Conference organisers say the protest action is based on misconceptions about the mining industry.

"If we can't shut it down, at least we can disrupt it as much as possible" 'Blockade' spokesperson Emma Black explains why her climate change activist group is causing chaos at a Melbourne mining conference. pic.twitter.com/3RP0pddPsf — Sunrise (@sunriseon7) October 28, 2019

They say the conference will consider the importance of battery minerals, used in the emerging electric car market, and the growing importance of ethical investment for resource companies, they said.

Victorian Premier Daniel Andrews said while protesting was a democratic right, violence was not acceptable.

“That’s a difficult balance sometimes, but I’m confident Victoria Police can find that balance,” he said.

Earlier, Deputy Prime Minister Michael McCormack described the protests as “disgraceful, absolutely disgraceful”.

-with AAP