"Six members of the Revolutionary Guards were killed in clashes with PJAK rebels in the region of Sardasht" a town 10 kilometres (six miles) from the Iraqi border in the West Azarbaijan province, Mehr said.

It said two soldiers serving as border guards were killed in the same region after stepping on mines "laid by the counter-revolutionaries." No further details were given.

The Party of Free Life of Kurdistan (PJAK) operates from rear-bases in northeastern Iraq and makes sorties across the border into Iran. It has been involved in a series of clashes with Iranian security forces in recent years.

The rebel group has close links to the Kurdistan Workers' Party (PKK), which has waged a deadly insurgency in southeastern Turkey since 1984.

Reports last week said that the Revolutionary Guards had killed nine Kurdish rebels, five of them women, in clashes in West Azarbaijan province near the border with Turkey.

An official newspaper then reported that three Revolutionary Guards were killed after sustaining injuries in fighting with rebels in northwestern Iran but it was not clear if it was referring to the same clash.

Iran has a substantial Kurdish minority in its northerwestern provinces. It also has minority populations of Baluch in the southeast and of Arabs in Khuzestan province in the southwest.

Iranian officials have accused Britain and the United States of being behind outbreaks of violence in these areas.