A suicide bomber driving a truck attacked a security checkpoint on a strategic highway south of Iraq's capital on Sunday killing at least 60 people.
Another 60 were wounded in the massive blast near the city of Hilla, police officials said.
Al Jazeera's Jane Arraf said Hilla is about 90km south of Baghdad.
"It was apparently a suicide bombing that occurred at a checkpoint that is usually manned by Iraq soldiers and federal police forces. A long line of cars along that key road were also caught in the blast," Arraf said.
It wasn't immediately clear who launched the suicide attack.
The Islamic State of Iraq and the Levant (ISIL) group has recently carried out a string of deadly assaults against Iraqi security forces.
Over the past week, a double bombing at a market in Baghdad's Sadr city killed more than 70 people. The following day a suicide attack at a funeral north of Baghdad killed about 30.
| ISIL kills scores in bloody day of attacks across Iraq
Source: Al Jazeera