At least 28 people, including 12 children, have been killed in a suicide truck-bomb blast in the northern Iraqi town of Tal Afar.
Dozens were also wounded and 10 homes destroyed in Monday's attack in a crowded Shia area of the town and police said the death toll was expected to rise.
There were conflicting reports about the number of casualties, and a local police official said that 19 children were among the dead, the AP news agency reported.
"Rescue teams are still searching for casualties among the rubble," said Ali Abbo, head of a human rights committee in the town.
The attacker drove a dump truck filled with explosives and covered with construction materials said Brigadier-General Rahim al-Jibouri, commander of Tal Afar police.
"I was sitting at home when I saw a big truck speeding along. I went outside to watch and suddenly it exploded, its contents flung everywhere," Abu Qassim said from his hospital bed in the northern city of Mosul.
"My house was destroyed. My wife and four of my children were injured as well as me," he said.
Within an hour of the attack in the Saadeh district, the authorities imposed a complete curfew on the city, al-Jibouri said.
Tal Afar - a town which the US military initially cited as a success story after it said its operations cleared the city of Sunni fighters - has been the site of frequent attacks in the past year.
Many of them stemmed from allegations by a 50-year-old Sunni Arab woman, who said last February that Iraqi soldiers raped her when they raided her house searching for weapons.
Sunni fighters have kidnapped and killed dozens of Iraqi security officials in response.
Meanwhile in Baghdad, a roadside bomb killed at least five people and wounded eight during rush hour, police said.
The bomb had been planted at the Zaafaraniyah intersection in the Jisr Diyala area, a predominantly Shia area.
The device, hidden on the side of the road, blew up after a minibus stopped to collect waiting passengers in the Diyala Bridge neighbourhood in the southern suburbs, security officials said.
Shrapnel sprayed the area as Iraqis got on and off the bus shortly before the main rush hour.
In the Sunni Arab heartland north of the capital, mortar rounds crashed through private homes, killing six civilians and wounding another 17 in the town of Dhuluiyah, the local police chief and hospital director said.