Pakistani police say dozens of militants have attacked a power station in the country's volatile northwest.
At least seven people were killed after militants attacked the facility with mortars and rocket-propelled grenades.
At least four others were missing after being kidnapped from the Shaikh Muhammadi Grid Station, near Peshawar, the capital of the restive Khyber Pakhtunkhwa Province.
Many parts of Peshawar were left without power after the predawn assault.
In an interview with Reuters television, Peshawar Electric Supply Company spokesman Shaukat Afzal said the power station had been completely destroyed.
"The restoration [of power supply] is going to take time because the damage to the station is total," he said.
Mohammad Ishaq, a senior police officer, said a policeman and a security guard were killed in the initial attack.
Ishaq said five others were taken hostage during the raid and later killed.
Their bodies were found in a field about 1 kilometer from the power facility. No one has yet claimed responsibility for the attack.
Ali Gohar, a spokesman for Pakistan's Water and Power Development Authority (WAPDA), told RFE/RL's Radio Mashaal that employees announced a province-wide protest strike in the wake of the violence directed at the station's workers.
"WAPDA employees are angry over last night's incident," Gohar said. "The militants' attack is an injustice because the WAPDA employees' job is to run the power grid station. We condemn this attack."
Budh Bher, where the raid took place, sees frequent attacks blamed on Pakistani Taliban.
With reporting by dpa, Reuters, and RFE/RL's Radio Mashaal