Five Pakistani security personnel were killed and six others injured in a suicide attack in the troubled north-western Swat valley on Monday.
A suicide bomber rammed his explosive-laden vehicle into a roadside checkpost in Madian town late tonight, officials said.
The blast also damaged nearby structures.
The Swat valley in the North West Frontier Province is a stronghold of local Taliban militants, led by radical cleric Maulana Fazlullah.
The attack came two days after the deadly bombing of the Marriot hotel in Islamabad which left 53 people killed.