Unidentified gunmen have shot dead a member of a banned Pakistan Sunni militant group in the north-western town of Dera Ismail Khan, police say.
Two men on a motorbike, one in a full veil, killed Masroor Alam Alami as he walked to his shop, witnesses said.
The group to which he is said to have belonged, Sipah-e-Sahaba, has a history of sectarian attacks and was banned in 2002 for having links with al-Qaeda.
It is suspected of involvement in a string of recent bombings in Pakistan.
The BBC's Haroon Rashid in Peshawar says Mr Alami was recently acquitted of charges that he had killing members of the minority Shia Muslim community.
Mr Alami had just left home for work when the attack took place.
Witnesses said the assailant who shot him was in an all-covering veil of the type worn by many women in Pakistan and Afghanistan.
Dera Ismail Khan has a history of deadly sectarian violence, our correspondent says.
Meanwhile, police in the neighbouring town of Tank say they have arrested a man with explosives.
Police have identified the man as a 28-year-old called Waheedullah.
They say they found him in possession of 30kg of explosive material, a detonator and jackets which could be used in suicide bombings.
Police say he is a close relative of tribal militant Abdullah Mehsud.
Mehsud is wanted for the October 2004 kidnapping of two Chinese engineers.
One of the engineers was later killed during a rescue attempt.