The move was aimed at accepting the demands of Shiites, who wanted troops to be deployed for their protection. Under law, only police can arrest criminals.
It was unclear what kind of powers would now be given to paramilitary forces in Baluchistan.
Many attacks against Shiites are carried out by Lashkar-e-Jhangvi, a militant group allied with al-Qaida and the Taliban.
Pakistan has a history of sectarian violence. Although most majority Sunnis and Shiites live together peacefully, small extremist groups on both sides often target each other's leaders and activists.
Also Saturday, a roadside bomb struck a vehicle carrying a local lawmaker, Shakeel Khan Omarzai, his father and his guards in the northwestern district of Charsadda. Omarzai and 10 others were injured in the explosion, senior police officer Nisar Khan said.
Omarzai is from the ruling Awami National Party. The party's senior leader, Bashir Bilour, was killed in a suicide attack at a rally on Dec. 22 in Peshawar, the capital of northwestern Khyber Pakhtunkhwa province.
The Taliban claimed responsibility for that attack.
Associated Press Writer Riaz Khan contributed to this report from Peshawar.