Eight school teachers were killed on Thursday in two separate incidents of targeted shooting in Pakistan's restive northwestern tribal district, bordering Afghanistan, in a case of possible sectarian violence, police said.

A school teacher, identified as Muhammad Sharif, belonging to Teri Mengal tribe (Sunni tribe) was killed when his car was ambushed by unknown gunmen on Shalozan Road in Parachinar headquarters of the Upper Kurram tribal district in the Khyber Pakhtunkhwa province, police said.

The incident angered Teri Mengal tribesmen who stormed the staffroom of the Govt Teri Mengal High School in the same district to avenge the killing of Sharif and killed seven teachers from Tori tribe (Shia tribe), police added.

All the teachers were at the school to perform their exam duties.

The attackers fled after the attack.

No group or individual claimed responsibility for the attacks, but the region is known for sectarian clashes between Sunnis and Shias.

An emergency has been declared in all the health facilities of the district. The Kohat Board exam for 9th and 10th grades has also been postponed after the killings.

Syed Zahid Hussain, President All Khurram Teachers' Association told PTI that all schools will remain closed till the arrest of accused involved in the killing of seven teachers.

The police have launched a massive hunt to arrest the killers.

The incident also comes just two days after Pakistani security forces killed Abdul Jabar Shah, a notorious Tehreek-i-Taliban Pakistan (TTP) commander and two others and made several key arrests in the Khyber Pakhtunkhwa province.

President Arif Alvi condemned the incident and expressed hope that the culprits would soon be arrested and punished according to law.

Pakistan Peoples Party co-chairman and former president Asif Ali Zardari also condemned the incident and demanded that the authorities take action against the attackers.

Separately, at least six soldiers and three terrorists were killed during a shootout between security forces and the terrorists in the North Waziristan tribal district, the army said.

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