As many as 16 people were killed and 25 injured as clashes between rival tribes which were triggered by a recent armed attack on two passenger convoys in Kurram District claimed 44 lives, continued on Saturday, reported 24NewsHD TV channel.
The deadly gunbattles between Alizai and Bagan tribes were reported from Balishkhail, Kharkali, Kunj Alizai and Maqbal village in Tehsil Lower Kurram of Parachinar, the main town in Kurram District.
The opponents were freeing using heavy and automatic weapons against each other.
All the educational institutions were shut down in Kurram District owing to the deterioration in the law and order situation.
Thousands protest across Pakistan
Thousands of protesters took to the streets in various cities of Pakistan on Friday, a day after sectarian attacks in the Kurram killed 44 people, including six women and five children.
Gunmen opened fire Thursday on two separate convoys of passengers travelling with police escorts in Kurram.
Several hundred people demonstrated in Lahore on Friday.
"We are tired of counting the bodies. How long will this bloodshed continue?" Khanum Nida Jafri, a 50-year-old religious scholar protesting, told AFP.
"Do our officials not consider Shias as part of their own population? When will they wake up?" he said. "We are demanding peace for our children and women. Are we asking too much?"
Hundreds also demonstrated in Karachi.
In Parachinar, thousands participated in a sit-in, while hundreds attended the funerals of the victims, resident Muhammad Ali told AFP.
"Following the funerals, the youth gathered, chanted slogans against the government, and marched toward a nearby security checkpoint," Ali said.
A senior administration official, speaking on condition of anonymity, told AFP that "some broke CCTV cameras at the checkpoint... burned tyres and caused damage to property", before the situation de-escalated.
Mobile phone signal across the district was shut down for several hours, according to the official.
"A curfew has been imposed on the main road connecting Upper and Lower Kurram, and the bazaar remained completely closed, with all traffic suspended," he said.
- Tribal feuds -
Clashes have erupted over several months between Sunni and Shia tribes in the area. Tribal and family feuds are common in tribal areas.
Thursday's attacks also left 16 people wounded, 11 of whom were in critical condition, senior administrator Javed Ullah Mehsud told AFP.
Mehsud said that a local jirga, or tribal council, has been convened to help restore peace and order.
Previous clashes in July and September killed dozens of people and ended only after a jirga called a ceasefire.
Reporter Mohsin Shirazi/AFP