An umbrella organization representing activist groups is launching a public campaign against Canada's security agency, accusing it of harassing and threatening its members.

The People's Commission Network says it has the support of nearly 70 collectives, federations and unions and wants its members to stop co-operating with the Canadian Security Intelligence Service (CSIS).

The group launched the campaign at a Montreal news conference Sunday afternoon.

Dolores Chew, who works with a South Asian women's organization in Montreal, says many members of the People's Commission have been visited by agents at their homes.

Chew accused CSIS of trying to take advantage of already vulnerable new female immigrants.

The security agency has recently gone after anti-capitalists, First Nations and student groups, the People's Commission alleges.

The group is urging its members to avoid CSIS agents if they approach them.

"CSIS plays a quiet but key role in creating a climate of fear and suspicion that legitimizes racism, the repression of dissent and increases in state power," the group states on its website.

With files from The Canadian Press