Amnesty International said Thursday evidence indicates Chile's security forces are linked to clandestine groups that have carried out more than 100 assaults or kidnappings in the past 18 months.

Hundreds of government opponents have received death threats as the clandestine groups have become a major force of political repression, the London-based international human rights group.Amnesty said Chile's military government blames the attacks and threats on ordinary criminals or independent extremist groups. But it said there is "convincing evidence" they are in fact carried out by groups linked to the security forces.