Peshawar, March 14 -- A blast ripped through a mosque on Friday in Pakistan's Khyber Pakhtunkhwa province, injuring at least four people, including the district emir of Jamiat Ulema Islam-Fazl (JUI-F), police said.

Abdullah Nadeem, a leader of the JUI-F, was believed to be the target of the blast in the South Waziristan district, and had been hospitalised with serious injures, said DPO Asif Bahadur, GeoTV reported..

He added that two children were among the injured. It was not immediately clear who was behind the explosion.

Attacks have been escalating in Pakistan's border regions with Afghanistan in recent months.

Last month, a suicide bomber killed six worshippers Maulana Hamidul Haq Haqqani - son of Maulana Samiul Haq and chief of hi...