Five killed in checkpoint attack
At least five security troops were killed when some 200 militants streamed over the border from Afghanistan and attacked a Pakistani checkpoint, police have said.
Local police official Bahadur Khan said the attack took place at around noon local time in the Upper Dir district.
A shoot-out was still going on an hour later at the scene in Shaltalo town, which borders Afghanistan's Kunar province.
Upper Dir lies just outside the border regions known as Pakistan's tribal areas. But it, too, has witnessed al Qaida and Taliban militant activity, and the Pakistani military has carried out operations there in the past.
Securing the long, porous border which divides Pakistan and Afghanistan has been a major challenge for the two countries as they try to stop insurgents.
The attack is the latest bloodshed as the Pakistani Taliban and affiliated groups carry out threats to avenge the May 2 US raid which killed Osama bin Laden in north-west Pakistan. But it is more likely a reaction to ongoing Pakistani military offensives against insurgents along the border.
The US has hailed Pakistan's operations against insurgents, which have been carried out primarily in the semi-autonomous tribal areas and have targeted militants attacking the Pakistani state.
But Pakistan has, at least publicly so far, resisted American appeals to stage an offensive in the North Waziristan tribal region, the primary haven for militant groups that attack US and Nato forces across the border in Afghanistan.