Attacks in Pakistan's southwestern province of Baluchistan killed 12 people on Thursday, police said.

The attacks included an assault on Pakistan's minority Shiites Muslims and a suicide bombing that targeted a pro-Taliban cleric. All the attacks took place in the provincial capital of Quetta where gunmen were seen chasing two fleeing victims as they fatally shot them down.

Six men died on board a bus that the gunmen shot at multiple times near a vegetable market. Two were wounded. Police helped them and removed the dead bodies from the bus.

Hundreds of Hazara Shiites crowded the main road in Quetta to protest the mass killing.

Police Chief Aitzaz Goraya said it was not clear who was behind the attack, and no one immediately claimed responsibility for it. Yet, Sunni extremists are likely to take the blame due to their track record of targeting Shiites in the past.

Sunni militant groups Lashkar-e-Jhangvi and the Pakistan claimed attacks on Shiites in the past. Over the last 10 years, the Taliban have been waging a war against the state in North Waziristan near the Afghan border. It killed thousands of Pakistanis in efforts to impose their harsh brand of Islamic law.

Baluch separatist and nationalist groups, based in Baluchistan, have been fighting for autonomy and a greater share of revenues from the region's natural resources. Earlier in October, a suicide bombing killed five Hazara.

Police reported that because of the former known attacks, the Hazara are usually given police escorts to and from destinations. Goraya said the Hazara targeted Thursday did not inform police of their travels.

More attacks followed on Thursday with one killing two civilians and wounding 10 and another killing two more and wounding many.

Attackers targeted the chief of the Taliban-linked Jamiat Ulema-e-Islam religious party, Maulana Fazlur Rehman with a suicide bomb. He survived the attack.