Explosion caused by IED fitted inside vegetable cart, says Parachinar DSP Najab Ali.
Bullet-riddled bodies of 3 employees and an FC official found burnt inside a torched vehicle in Spin Wam tehsil.
Search operation underway for attackers.
Another security forces personnel injured in firing originating from Afghanistan, sources say.
Area cordoned off, investigations into the incident underway.
The facility will be used to educate the district's female voters about their electoral rights.
One other injured in the blast in Upper Kurram's Basu area.
A suspected Haqqani Network commander, and two others were allegedly killed in the drone strike.
One man injured in Kurram Agency, two killed in Afghanistan's Khost province.
Eyewitnesses day the strike targeted a vehicle in the Mata Sangar area of Kurram.