Pakistani officials say 40 people were killed and at least 40 others wounded in fierce sectarian clashes in a remote northwestern town.
A military-imposed curfew is in place in Parachinar, in the semi-autonomous Kurram region, after gunbattles erupted Friday between Sunni and Shi'ite Muslims.
The cause of the violence has not been independently confirmed. But residents have said the trouble began when one group held a demonstration denouncing the other sect.
An official in the tribal region Sahibzada Mohammad Anis on Saturday told reporters that army helicopters are patrolling the area. Authorities say soldiers have been given shoot-on-sight orders.
The town of Parachinar is located about 250 kilometers southwest of Peshawar, the capital of North West Frontier province.
Thousands of people have been killed in sectarian violence between Sunnis and Shi'ites in Pakistan since the 1980s.