More than 60 people were killed in a series of car bomb explosions targeting Shiite Muslims across Iraq on Monday, police and medics said, part of the worst sectarian violence since US troops pulled out in December 2011.

The attacks brought the number killed in sectarian clashes in the past week to over 200.

No group claimed responsibility for the bombings. Iraq is home to a number of Sunni Islamist insurgent groups, including the Al Qaeda-affiliated Islamic State of Iraq, which has previously targeted Shiites in a bid to provoke a wider sectarian confrontation.

Nine people were killed in one of two car bomb explosions in Basra, a predominantly Shiite city 420 kilometers southeast of Baghdad, police and medics said.

"I was on duty when a powerful blast shook the ground," said a police officer near the site of that attack in the Hayaniya neighborhood.

"The blast hit a group of day labourers gathering near a sandwich kiosk," he added, describing corpses littering the ground.

"One of the dead bodies was still grabbing a blood-soaked sandwich in his hand."

Five other people were killed in a second blast inside a bus terminal in Saad Square, also in Basra, police and medics said.

In Baghdad, at least 30 people were killed in car bomb explosions in Kamaliya, Ilaam, Diyala Bridge, al-Shurta, Shula, Zaafaraniya and Sadr City - all areas with a high concentration of Shiites.

A parked car bomb also exploded in the mainly Shiite district of Shaab in northern Baghdad, killing 12 people and wounding 26 others, police and hospital sources said.

In a separate incident, police said that a parked car blew up near a bus carrying Shiite Muslim pilgrims from Iran near Balad, located 80 kilometers north of Baghdad, killing five Iranian pilgrims and two Iraqis who were traveling to the Shiite holy city of Samarra.

In the western province of Anbar, the bodies of 14 people kidnapped on Saturday, including six policemen, were found dumped in the desert with bullet wounds to the head and chest, police and security sources said.

Reuters