Police in southwestern Pakistan say gunmen opened fire on a minibus Saturday, killing 11 Shi'ite Muslims, including one woman.
Officials say at least two people were wounded in the suspected sectarian attack in Quetta, the provincial capital of Baluchistan.
Hundreds of people staged a demonstration outside a Quetta medical complex to protest the attack, torching two cars and two motorcycles. Authorities say the police have regained control of the situation.
Pakistan has a history of sectarian violence. Although most majority Sunnis and Shi'ites live peacefully together, small extremist groups on both sides often target each other.
A separatist insurgency and criminal groups also are active in Baluchistan.
On Friday, unknown gunmen killed seven people at a bus terminal in Quetta. The victims were waiting for a bus heading to neighboring Iran, and included some people of non-Baluch origin.
Some information for this report was provided by AP, AFP and Reuters.