Michael Moore joined anti-Wall Street protesters at Occupy Oakland on Friday, urging the crowd of about 1,000 to continue their demonstration.
"We've killed despair across the country and we've killed apathy." Moore said to the crowd, CBS News reports. "I've never seen a movement take form so fast."
Moore is known for his political documentaries such as "Fahrenheit 9/11" and won an Oscar for his 2002 movie "Bowling For Columbine." The filmmaker has been fighting big business for most of his career and was welcomed warmly by the protesters.
"Millions have seen this and are inspired by you because you came back the next night," Moore continued.
The Occupy Movement began as a demonstration against what protesters see as a growing disparity between rich and poor, which has left much of the country impoverished and jobless.
Occupy Oakland demonstrators faced off against police earlier in the week, which left 24-year-old Iraq War veteran Scott Olsen with a fractured skull.
Moore said of Olsen, "It's absolutely criminal that this young man went to Iraq for a war he didn't agree with, and the only place he had to worry about was here in his own country, in Oakland, California."
Police were criticized for firing tear gas and bean bags at protesters on Tuesday evening. Oakland's police chief said he takes responsibility for the crackdown on the protestors.
"I want to ensure you that all allegations of misconduct and excessive uses of force are being thoroughly investigated," Oakland Interim Police Chief Howard Jordan told the Associated Press.
Protesters have been camping out in tents for six weeks and the Occupy protests, which were initially dismissed by politicians and bankers have sparked national debate.
The demonstrations were initiated by the Canadian activist group Adbusters, primarily to protest social and economic inequality, corporate greed, corruption and the financial sectors influence over the government.
Occupy Wall Street began on September 17 and by October 9, similar demonstrations had begun in 70 major cities and over 600 communities in the United States. Internationally, another 900 cities worldwide organized Occupy protests.
"When was the last time in the last few weeks you heard them talking about the debt ceiling?" Moore asked the crowd, the Associated Press reports.
Moore is known for his views about the government's handling of its war on terrorism, its treatment of America's poor and other social and economic issues.
In December, he made headlines after he pledged support to WikiLeaks founder Julian Assange, who has angered U.S. officials by publishing classified diplomatic papers. Moore said Assange's organization had "saved lives".
Watch a clip from Michael Moore's speech at Occupy Oakland below.