Climate activists have kicked off another wave of disruptive protests in the heart of Melbourne, this time targeting a mining conference attended by thousands of global delegates.
Activists are hoping to shut down the International Mining and Resources Conference at the Convention Centre, which starts on Tuesday.
A group of about 100 people made their presence known outside the facility on Monday before marching up Spencer Street, temporarily delaying traffic.
Police say 11 different groups plan to cause "maximum disruption" outside the conference, with protests likely to continue spilling across parts of the CBD.
More than 300 police officers will be assigned each day to ensure activists don't break the law or adversely impact the community.
The Extinction Rebellion group ran a week of climate protests early in the month and Victoria Police acting commander Tim Tully said activists might ramp up their methods this time.
"We expect to see heightened tactics by the protest groups," he told reporters in Melbourne on Monday.
"Our intelligence would suggest that the protesters have been planning, and are well co-ordinated, to undertake different tactics to what we saw, or very similar tactics to what we saw, in the recent protest activity.
"We are well prepared to respond."
A spokeswoman for one of the groups, IMARC Alliance, said they aren't planning to cause havoc in the CBD.
"It's never been our intention to disrupt the city ... we want to shut down the conference using blockading tactics," Emma Black told 3AW.
"Our enemy are not motorists or the police, our enemies are the corporate mining executives."
But her group can't control the likes of Extinction Rebellion, she said.
Acting commander Tully said protest groups have been unwilling to give police a good sense of what they can expect to deal with.
"It's been very frustrating, the lack of engagement that we've had," he said.
A statement released by conference organisers said they welcomed the protesters' right to make their views known, "but not to cause disruption".
"Just as those outside have the right to protest peacefully, the 7000 experts from across the globe have the right to meet to discuss mining", a spokesperson said.
Victorian opposition leader Michael O'Brien said people should be allowed to go about their business without being confronted by "constant demonstrations".
"It's turning Melbourne into a joke and unless the premier starts giving the police the powers they need to do with it, it's just going to continue and go on," he told reporters.
The mining and resources conference is scheduled to run for three days.
Australian Associated Press