Afghan officials said that Pakistani troops crossed on to Afghan soil, prompting a response by border forces and the local tribal force.
Troops from the Afghan border police and Pakistan's paramilitary Frontier Corps clashed near the two countries' disputed border, leaving several dead and wounded on both sides, Afghan and Pakistani officials said. There's now no information about the death toll on the Afghani side.
The ISPR added that the security personnel were plugging the gaps at the border and making necessary preparations to start fencing in that area to stop unwanted infiltration from the Afghanistan side.
Col. Abdul Hanan, interim chief of the Afghan National Police, said clashes broke out in the morning when Pakistani border forces allegedly opened fire at Afghan villages in Zazi Maiden district along the Durand Line.
The two US allies routinely accuse each other of failing to crack down on militants who operate along the porous border.
Kurram is one of the most sensitive tribal areas as it borders three Afghan provinces and at one point was one of the key routes for militant movement across the border.
Khost provincial governor spokesman Talib Mangal confirmed the incident, but said two Afghan civilians and four Pakistani troops were killed. It added that hundreds of mortars had been fired by Pakistani forces on another Afghan province of Kunar since early April.
Clashes are frequent in the area as Afghanistan doesn't recognize the 2,400-kilometer Durand Line (drawn by Britain in 1896) as its global border with Pakistan.