A government official says 23 militants were killed in clashes with a pro-government tribal militia in northwest Pakistan.

Syed Ahmad Jan, a senior local administrator, said Tuesday the clashes took place in the village of Ambar in the Mohmand region, part of the lawless tribal belt along Pakistan's border with Afghanistan.

Jan said that four members of the tribal militia were wounded in the clashes, which began late Monday and continued through Tuesday morning.

The government has encouraged tribesman in the semiautonomous frontier region to form local militias -- known as lashkars -- to repel Taliban militants blamed for attacks in Pakistan and in neighboring Afghanistan.

Such groups have been set up in several regions but face stiff Taliban resistance.