At least 30 people were killed and 27 wounded when a car bomb exploded outside a hospital in a town south of Baghdad, officials say.
Civilians and children bore the brunt of the bomb attack
The bomb was detonated as two Iraqi police cars drew up near the general hospital in Mahmudiya, about 20km (12 miles) outside Baghdad.
A US military convoy passing by was also hit by the blast.
On Thursday evening a car bomb exploded in a busy market in Hilla, killing at least two people and injuring more.
At least 13 were injured in the blast, which occurred when a parked car exploded at about 1800 (1500 GMT) in the mainly Shia town, police said.
Mahmudiya is a mixed Sunni-Shia town in a region where insurgents have launched many attacks on US-led forces.
"At this time it appears that four of our soldiers were wounded but they are not life-threatening injuries," Sergeant David Abrams said of the US troops hurt in the attack.
Several Iraqi policemen were killed in the blast.
Women and children were also among the many civilian casualties, including at least one medic at the hospital's emergency centre.
"I was leaving the hospital with my one-and-a-half-year-old son in my arms when the explosion happened," Huda Ali told the AFP news agency.
"I was knocked down by the force of the blast and when I came to, my son was no longer in my arms. I found him among the dead."
The BBC's correspondent in Baghdad, Jim Muir, says that unlike many of the horrendous bomb attacks over the past week, the attack in Mahmudiya does not seem to have been aimed at the civilian population as such but at the Iraqi police.
Nonetheless, it is the civilians who have paid the bulk of the price, our correspondent says.
'Insurgents' last stand'
Laith Kubba, spokesman for Iraqi Prime Minister Ibrahim Jaafari, told reporters that insurgent attacks are likely to increase in the run-up to December's parliamentary elections.
He predicted that Muslim extremists and militants loyal to Saddam Hussein would make their last stand.
"Muslim extremists will be surrounded then wiped out," Mr Kubba said, although he conceded that it would not happen quickly.
In other developments, three US soldiers from Task Force Baghdad were killed in two separate attacks on military patrols in Baghdad on Wednesday, the US military said in a statement.
One soldier was killed in central Baghdad, while two others were killed in the south-west of the city.
An Iraqi soldier was also killed on Wednesday when a roadside bomb exploded in Khalidiya, near Falluja, police said.