CHICAGO: Anti-war protesters have claimed their homes and offices were raided by the FBI on Friday in an attempt to silence dissent in the US.

An FBI spokesman confirmed agents searched six locations in Minneapolis and two in Chicago as part of an investigation into ''activities concerning the material support of terrorism''.

Special Agent Steve Warfield of the Minneapolis branch of the FBI declined to confirm who was raided, saying only that the warrants remained sealed. ''There's no imminent threat to the community,'' Warfield said. ''We did not plan on making any arrests and we did not make any arrests.''

Activist Mick Kelly, an organiser of a huge anti-war rally on the opening day of the 2008 Republican National Convention, said the FBI had kicked down his door about 7am on Friday after he had already left for work.

''To me this is harassment of anti-war activists and leaders who have spoken against US intervention in Latin America and the Middle East,'' Kelly said. He insisted he had ''absolutely not'' been involved in any illegal activities.

Activist Jessica Sundin said the FBI had taken her mobile and given her a subpoena to testify before a grand jury in Chicago, and was looking for items related to her anti-war activities and trips to Colombia and the Middle East.

''I am angry,'' she said. ''I want people to know that the government is targeting people for our ideas.''