Updated: 2007-10-26 16:02

Local residents examine the site of Thursday's suicide bombing in Mingora, the main town of Swat mountainous area of Pakistan's North West Frontier Province bordering Afghanistan, Friday, Oct. 26, 2007. Pakistani security officials investigated the scene of a deadly suicide attack that killed 20 people in northwestern Pakistan, just days after troops were sent to the lawless region to quell pro-Taliban militants. [Agencies]

PESHAWAR, Pakistan -- Security forces opened fire Friday on a stronghold of a militant cleric in northwestern Pakistan, sparking a fierce gunbattle near the scene of a suicide attack on a military truck that killed 20 people, police said.

"The security forces attacked a building where Maulana Fazlullah had been appearing in recent days to urge his followers to target Pakistan army, police and other security forces," said Muhib Ullah, a local police official.

There was no immediate word on casualties.