Militants on Saturday shot dead prominent religious scholar and Swat Islamic University Vice-Chancellor Farooq Khan and his aide in Pakistan's troubled northwest, police and witnesses said.
The attack was carried out by three men armed with Kalashnikov assault rifles.
The gunmen came to the clinic of Khan, who was a psychiatrist, in Mardan city, located 65 km from Khyber-Pakhtunkhwa capital Peshawar, and disarmed his bodyguards.
The attackers then entered the clinic and fired indiscriminately, killing Khan and his assistant Saleem Khan.
No group claimed responsibility for the attack. The attackers fled after the incident.
Khan, who was well versed in Shariah or Islamic law, had been critical of extremism and militancy.
He was associated with the Jamaat-e-Islami party in the past and contested elections to a parliamentary seat from Mardan in 1993. He quit the Jamaat-e-Islami in the 1990s.
Family sources said Khan had no enmity with anyone.
Sources said he had been receiving threats from unidentified persons for some time.
His killing sent a wave of shock across the country as he was highly respected for his social and educational activities. Khan was the author of several Islamic books and a transcription of the holy Quran.
He also anchored Islamic programmes on TV channels.
He was appointed the first Vice-Chancellor of the Swat Islamic University that is yet to begin functioning.
The government selected Imamdheri madrassa, the former headquarters of Taliban commander Maulana Fazlullah, for setting up the university.
Prime Minister Yousuf Raza Gilani strongly condemned the killing of Khan, describing him as a renowned religious scholar.
He lauded Khan's services for promoting education in underdeveloped areas of Khyber-Pakhtunkhwa and in suggesting changes in the curricula in accordance with Islamic teachings.
While reaffirming his government's resolve to fight terrorism, Gilani said the administration is committed to eradicate the menace of terrorism in all its forms at all costs.
"Those elements which are playing with the lives of innocent people would not escape the law of the land," he said.