BAGHDAD — The Islamic State claimed responsibility on Saturday for the bombing of a minibus that killed 12 people near the entrance to a major Iraqi pilgrimage center.

The attack was one of the most lethal since the fall of the Islamic State’s de facto capital at the end of 2017, according to the Iraqi Security Forces.

It was also one of the few Islamic State attacks south of Baghdad since the group’s self-declared caliphate collapsed. It brought back memories of the period after the fall of Saddam Hussein in 2003, when Shiite pilgrims were routinely targeted south of the capital as they traveled to shrines in the cities of Karbala and Najaf.

The bomb, left on the minibus by a passenger, exploded at a checkpoint at one entrance to Karbala near midnight on Friday. It killed 12 people, wounded five and demolished the bus.