Soldiers were called out after gunbattles between Sunni and Shia Muslims in Parachinar, a town in the semi-autonomous Kurram region, local administration official Nasim Khan told AFP.

"Troops have taken up positions in the area and a curfew has been imposed in the town," he said. "Fighting is still going on in different parts of the city."

Three people died and 13 others were injured in the violence Friday, hospital sources said.

Khan said trouble erupted on Friday when members of the minority Shia sect staged a demonstration outside their mosque against local Sunnis who allegedly chanted anti-Shia slogans during a religious rally last week.

Rival groups went on the rampage in the main bazaar and torched a commercial building and several shops, Khan said.

Parachinar, bordering eastern Afghanistan's Paktia province, has a large Shia population. Clashes between the two communities over a shrine in the tribal areas last year left around 20 people dead.