Story highlights

A bus carrying Shiites on a religious pilgrimage is attacked, police say

"This was a sectarian terrorist incident," says senior police official Shanawaz Khan

CNN  — 

A bus carrying Shiite Muslims was attacked Tuesday evening, killing 26 and wounding six, near the garrison city of Quetta in southwest Pakistan, senior police official Shanawaz Khan told CNN.

“This was a sectarian terrorist incident” said Khan, who added the passengers were on a religious pilgrimage to Iran when unknown assailants began firing on the bus.

The Mastung District, an area 40 kilometers (25 miles) south of Quetta, where the attack happened, has been the site of frequent violence between extremist Sunni and Shiite Muslim factions.

The attack on the bus was followed by another assault in Akhtarabad, a suburb of Quetta, where three men were shot in a vehicle, senior police official Hamid Shakeel told CNN.