The development comes a day after the family of Anwar Jan accused Abdul Rehman Khetran, a minister for food in Baluchistan province, of hiring gunmen to kill Jan on Thursday.
Police officer Abdul Aziz said a murder investigation has been opened into Khetran’s possible involvement. Khetran has denied being involved, saying the gunmen blamed by Jan’s family for killing him were not his men.
Repeated attempts to reach Khetran for comment were unsuccessful.
Jan was killed by two gunmen as he was walking to his home in the town of Barkhan. His family insists Khetran ordered Jan’s murder in retaliation for Jan exposing alleged corruption.
Pakistan is considered to be one of the most dangerous places for journalists, and attacks on them are not uncommon.
Anwar Jan’s killing comes days after prominent Pakistani journalist Matiullah Jan, who is unrelated, was abducted in broad daylight in the capital Islamabad. His abductors freed him in a deserted place 12 hours later.
The government has not said who was behind Matiullah Jan’s abduction.
Also on Saturday, Pakistan’s military said gunmen opened fire on a security vehicle as it patrolled the area of Pidarak in Baluchistan, killing a soldier and wounding three others.
The military said troops in a raid elsewhere in Baluchistan killed a key leader of the separatist Baluch Liberation Army and foiled a possible attack by seizing a cache of weapons.
Baluchistan has for years been the scene of a low-level insurgency by separatists who complain of discrimination and demand a fairer share of the province’s resources and wealth. Militants also have a presence in the province.