At least four Pakistani paramilitary soldiers have been killed in a suicide attack in the troubled northern district of Swat, army officials say.
The attack took place at a security checkpoint when a car carrying the bomber rammed into it.
Swat has been the scene of an insurgency since August 2007.
Hundreds of people have been killed since then in battles between security forces and militants led by a Taleban cleric, Maulana Fazlullah.
"The attack left four soldiers dead, while three others were injured," Col Atiq-uz-Zaman, a spokesman for the Pakistan army told the BBC Urdu service.
Pakistani forces have been fighting militants in Swat since last year
"The attacker rammed his vehicle into a security checkpoint near Khwazakhela".
Khwazakhela is a sub-division of Swat which has seen a number of battles between the two sides.
The militants say they are fighting for the enforcement of Islamic Sharia law in Swat.
Maulana Fazlullah is also demanding that the army withdraw from Swat.