Four bomb blasts rocked Karbala on Sunday, killing at least 10 people less than two weeks after 22 pilgrims from the Shiite holy city were shot to death in a bus hijacking in remote western Iraq.

The explosions took place in an area of Karbala close to an Iraqi government building where ID cards are issued. The attacks, in which at least 95 people were injured, occurred during rush hour.

Prime Minister Nouri Maliki, a Shiite Muslim, called the bombings "gruesome" and promised a thorough investigation. "We will hit firmly anyone standing behind this crime and the previous crime," he said in a statement issued by his office.

Maliki sent a Cabinet-level delegation to the city south of Baghdad to inspect the crime scene and offer condolences and help to the families of victims.

The bloodshed, the latest in a series of deadly attacks across Iraq, harks back to the days of civil warfare five years ago between Shiites and Sunni Arabs. It also underscores the increasing dangers faced by Iraqi officials as the U.S. winds down its military deployment in Iraq.