Story highlights

Five Pakistani security personnel are injured

The skirmish is the latest in a series of clashes

The withdrawal of U.S. troops has emboldened militants, Pakistan says

Tensions between Pakistan and Afghanistan are high

Islamabad, Pakistan CNN  — 

Seven Afghan militants were killed and five Pakistani security forces injured in a cross-border skirmish Friday, officials said.

It was the latest in a series of recent cross-border assaults from Afghanistan’s Pech Valley and the provinces of Kunar and Nuristan, all areas from which U.S. troops began pulling out earlier this year as part of a strategy designed to bolster security in more populated areas of Afghanistan.

The five injured Pakistani security personnel were airlifted by military helicopters to a base in northwest Pakistan, Col. Nasir Jadoon, commander of a border security force in Chitral, Pakistan, said.

The Pakistani forces returned fired into Afghanistan, killing seven militants, Jadoon said.

In the same border region in August, at least 25 Pakistani security personnel were killed when between 200 and 300 militants attacked border posts along Pakistan’s border with Agfhanistan. Those who died included Pakistani soldiers and police.

Pakistani military officials have said the withdrawal of U.S. troops has provided insurgents in the mountainous areas of eastern Afghanistan with safe havens to launch cross-border attacks against Pakistani security forces.

The attacks have raised tensions between Pakistan and Afghanistan, with each country accusing the other of not doing enough to secure its border region.

Journalists Saboor Khattak and Shaan Khan contributed to this report.