Two officers have been injured as protesters clashed with police in an effort to blockade the Melbourne venue for the World Economic forum.
Police have twice come head to head with protesters outside the Clarendon Street entrance to Crown Casino where the forum is being held.
Protesters claim the confrontations have been unnecessary.
"I was right there on the side and the police...they've achieved nothing except crushing a lot of people," one protester said.
The protesters believe they have succesfully blockaded every access point at the venue.
Earlier, they turned away bus loads of private security guards and forum delegates.
The Western Australian Premier, Richard Court, was among those turned away, as was the Victorian Opposition leader, Denis Napthine, whose official car was spray-painted with anti-forum slogans.
Violence broke out between police and protesters at one of the entrances to the casino.
It appears police were trying to get four buses through to the forum.
About 2,000 protesters gathered at the Kings Way access road to the casino and about 20 mounted police slowly charged the crowd without warning.
In a stand off lasting about 10 minutes, the protesters managed to push back the police.
More police on foot tried to squeeze the crowd from behind but were also overcome.
More mounted police have been called in to try and push protesters away from the barricades and allow four buses, possibly carrying forum delegates, through.
Stephen Spence, the chairman of the international committee with the South Australian United Trades and Labour Council, is at the protest and says the corporate executives are barricaded inside.
"At the taxpayers' expense the casino is protected from a crowd whose mood is good humoured and good natured," he said.
"At the moment people are chatting, standing in the rain because it's pouring down at the moment being Melbourne and getting their point across that globalisation is something that will have to take notice of ordinary people."
Greens' Senator Bob Brown, who is at the protest, says bad weather has not affected protest numbers.
"It's raining again at the moment and it's very cold so huge numbers, thousands of people [are] out - that's a tribute to this awakening people...want to close the gap between rich and poor instead of allowing it to continue to open," he said.
Monday 11 September, 2000
10:53am AEDT