A mob attacked a man accused of blasphemy during Friday prayers in a northern Pakistani town and injured six police officers after they intervened to rescue him.

It was the third blasphemy-related incident in the country this month after a student was beaten to death by a lynch mob and a faith healer was shot dead.

Security officials in Chitral fired tear gas and live rounds on the mob, injuring eight protesters, after they attacked the local police headquarters and demanded that alleged blasphemer Rashid Ahmed be made available for mob justice.

"We told them that Ahmed will be examined medically and if he was found mentally fit then he will be tried under the blasphemy law, but the mob was not satisfied," Akbar Ali Shah, the local police chief, said.

Shah said he had asked for army assistance to help control the crowds, but a Reuters news agency correspondent at the scene said soldiers had yet to arrive.

Witnesses said Ahmed entered the local mosque asking to make an important announcement, then declared himself a messiah and said he would lead his followers to paradise.

An angry congregation then turned violent and attacked Ahmed, who Shah said appeared to be suffering from mental illness. He suffered a beating, but police said his injuries were not life-threatening.

Women's confession

In a separate development on Friday, police in the capital Islamabad said three female friends in a rare incident had confessed to killing a man for alleged blasphemy, just days after he returned from living in hiding abroad for 13 years.

Police Inspector Nadeem Ashraf, who is investigating the case, told the Associated Press news agency that the women were arrested this week for killing Fazal Abbas, who fled Pakistan in 2004 following accusations of blasphemy.

Ashraf said the women went to the man's home and shot him to death on Wednesday.

Ashraf identified the women by their names and quoted them as saying that they would have killed Abbas earlier had he not fled the country.

Ashraf said Abbas was being sought by Pakistani police in connection with a blasphemy case dating back to 2004.

Blasphemy is an extremely sensitive issue in Pakistan. Insulting Prophet Muhammad carries a judicial death sentence and, increasingly, the threat of extrajudicial murder by vigilantes.

Nearly 70 people have been killed in connection with blasphemy allegations since 1990, according to a tally maintained by Al Jazeera.

Pakistan's government has been vocal on the issue of blasphemy, with Nawaz Sharif, the prime minister, issuing an order last month for the removal of blasphemous content online and saying anyone who posted it should face "strict punishment under the law".

Police are investigating more than 20 students and some faculty members in connection with the killing of Mashal Khan, a student who was beaten to death on April 13 in an attack that shocked the country.

Since then, parliament has discussed adding safeguards to the blasphemy laws, a move seen as groundbreaking in Pakistan where political leaders have been assassinated for even discussing changes.