The Taliban government has confirmed that it attacked Pakistani troops in multiple mountainous locations on the northern border.
Casualties are not yet clear in what the Taliban government called "retaliatory operations", after it claimed Pakistan had violated Afghan airspace and bombed a market inside its border on Thursday.
Pakistan's Interior Minister Mohsin Naqvi said the Afghan attacks were "unprovoked" and civilians were fired at, warning that his country's forces would respond "with a stone for every brick".
Islamabad has accused Kabul of harbouring terrorists who target Pakistan on its soil, a claim the Taliban government rejected.
Both the Afghan and Pakistani sides are said to have used small arms and artillery in the Kunar-Kurram region.
Author's summary: Taliban confirm retaliatory attacks on Pakistan.