At least 25 people have been killed in Pakistan's North West Frontier Province (NWFP) in clashes between supporters of rival Muslim clerics, officials say.

The factions fought pitched gun battles with automatic weapons in the town of Bara town in Khyber agency, tribal areas spokesman Shah Zaman Khan said.

Fighting began late on Monday after a house was demolished and continued until early Tuesday, Mr Khan said.

Reports say there has been tension between the factions for some months.

The BBC's Zaffar Abbas in Islamabad says the fighting has nothing to do with a security operation against pro-Taleban followers in nearby Waziristan and is more about territorial control and enforcing the conflicting Muslim beliefs of the two rival clerics.

'Tension and fear'

Fighting between the two groups has stopped and troops have been deployed in the area to maintain order, Khan said.

A jirga (tribal assembly) has also been called to try to calm the tension in the area, he said.

Hundreds of supporters of Mufti Munir Shakir attacked the stronghold of a rival Afghan preacher, Pir Saifur Rehman, on Monday killing at least 16 people, officials say.

"The fighting continued the whole night. There is tension and fear in the area," a local resident Sultan Khan Afridi told the Associated Press news agency,

Mohammad Nisar Afridi, a local trade union leader, told the Reuters news agency: "Dead bodies are still lying there and paramilitary troops have sealed off all roads leading to that place."

Both clerics have been operating illegal FM stations to broadcast their religious beliefs and label the rival group heretics.

The two groups have also accused each one another of taking women and children hostage.

Tension between the rival groups has risen sharply in the last few months after an earlier attempt to resolve the dispute through a jirga failed.

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