No soldiers died, but most of the casualties in the town of Mahabad were said to be women and children.

A provincial governor blamed "counter-revolutionary groups" for the attack, which came on the 30th anniversary of the start of the Iran-Iraq war.

Militants have long been active in the area, which is home to a sizeable Kurdish population.

The parade was one of a number being held across Iran as the country marked 30 years since the beginning of the Iran-Iraq war, a bitter conflict that ran from 1980 to 1988.

More than a million people died during the war.