QUETTA, Pakistan (Reuters) - Gunmen opened fire on a bus in Pakistan's southwestern province of Baluchistan in a suspected sectarian attack on Tuesday, killing at least 20 Shi'ite Muslim pilgrims traveling to Iran, police said.
The attack took place near Mastung town around 50 km from the provincial capital of Quetta.
Many pilgrims were wounded, said a police official.
Sunni Muslim militants loyal to al Qaeda and the Taliban have carried out high-profile attacks on members of Pakistan's Shi'ite minority in the past.
Pakistan has seen a surge in violence since al Qaeda chief Osama bin Laden was killed by U.S. special forces in a secret raid in a Pakistani town in May.
Militants have vowed revenge for bin Laden's death.
(Reporting by Gul Yusufzai; Writing by Zeeshan Haider and Sugita Katyal)