Malik Mushtaq, a Station House Officer who was presently posted with the National Accountability Bureau (NAB), was shot dead when he was offering prayers in a mosque in Chaman Patak in Quetta, a senior police official said.
He said that three armed men entered the mosque and gunned down Mushtaq who was offering prayers at that time.
"Mushtaq died on the spot after receiving several bullets in his chest," he said.
Police rushed to the spot soon after the incident and cordoned off the area while the deceased was shifted to the Civil Hospital, Quetta.
Last Wednesday, four Frontier Corp personnel were killed in an ambush on their vehicle in Quetta.
Reports say that around 35 police personnel have been killed in several cases of targeted killings and bomb blasts in the provincial capital since January 2016.