Twin car bombings have killed at least six people and injured about 50 in southern Iraq, officials say.
The near-simultaneous bombs went off in Kut, the capital of Wasit province, 100 miles (160km) south of Baghdad.
The bombings came hours after a series of smaller attacks targeting members of the security forces in Baghdad killed eight police officers.
The deaths have renewed concerns about security in Iraq, with US combat troops due leave the country later this month.
US President Barack Obama confirmed on Monday that US combat troops would leave Iraq at the end of August, asserting that violence was the lowest it had been for years.
Witnesses say the co-ordinated car bombs exploded in a crowded shopping area in the city of Kut.
Two cars parked a few metres from each other exploded at the same time in Kut's commercial centre, police spokesman Lt Ismail Hussein told AFP.
Local shopkeeper Nasir Salman said the blasts happened at about 1800 local time (1500 GMT) when the streets were crowded.
"I saw with my own eyes women and children lying dead and wounded on the ground," said Mr Salman, whose tyre shop was damaged.
Haidar Habib, a currency trader, said he had been "thrown to the floor" of his shop by the force of the explosions.
On Tuesday morning, five policemen were killed at a checkpoint in Baghdad by men using guns with silencers.
Witnesses said the black flag of the Islamic State of Iraq - a front organisation for al-Qaeda - was left at the scene, suggesting it was behind the attack.
Elsewhere in the capital, two police officers were killed as they tried to defuse a bomb in Sadr City in the eastern part of the Iraqi capital.
Another policeman was killed by an explosive device attached to his motorbike.
While violence in Iraq has fallen in the last three years, shootings and bombings still take place regularly.
The Iraqi Ministry of Interior says nearly 400 civilians were killed in attacks in July.
US and Iraqi officials have raised concerns that insurgents are taking advantage of the political vacuum in the country to try to destabilise it.
Nearly five months after Iraq's parliamentary elections failed to produce a clear winner, there is still no agreement on a coalition government.