Pakistani TV networks also reported an explosion in the Bannu area of the Khyber Pakhtunkhwa province.

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The Jani Khel tribe is located in the area of Bannu where the military dropped leaflets warning residents to leave.

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We later learned that networks had also been blocked in Bannu and the Lakki Marwat districts, both near the Waziristan region.

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The selected districts were: Chitral, Swat, Bannu, Charsadda, Mansehra, Mardan and Peshawar.

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One of the tribes, Jani Khel, has also been linked to numerous militant attacks on military bases in the Bannu area, Abbas said.

CNN: Blast kills cleric who denounced suicide attacks

He described Bannu as a "known and notorious hideout" for militants.

CNN: Blast kills cleric who denounced suicide attacks

"He said he was calling from Miranshah in North Waziristan and the telephone number used to make the call carried an area code common to the Waziristan tribal area and Bannu, the adjoining district in the North West Frontier Province, " the paper said.

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