QUETTA, Pakistan, Jan 21 (Reuters) - A bomb ripped through a bus full of Shi'ite pilgrims in western Pakistan and killed at least 22 people on Tuesday, police said, extending a spate of sectarian attacks that have shaken the South Asian nation.
The bomb exploded near a bus carrying pilgrims returning from neighouring Iran to their home city of Quetta in Pakistan, officials said. At least 20 people were wounded, said the assistant police commissioner for Mastung district, Shafqat Anwar Shawani, and many of the victims were women and children.
The attack occurred about 55 km (35 miles) southwest of Quetta, the provincial capital.
Sectarian attacks are on the increase in Pakistan, where minority Shi'ites make up about 20 percent of the 180 million people. Human Rights Watch said more than 400 Shi'ites were killed in 2013. They included many professors, doctors and children shot on their way to work or school. The violence is worst in the western province of Baluchistan.
Militant groups like Lashkar-e-Jhangvi say they are fighting for a Sunni theocracy and Shi'ites should leave the country or be killed.
Many sectarian groups are theoretically banned but their leaders still address rallies and grant interviews. (Reporting by Gul Yousufzai Writing by Maria Golovnina; Editing by Mark Heinrich)