There were no immediate reports of any US casualties.
Earlier, three civilians, believed to be street cleaners, were killed and four others wounded by a roadside bomb in Baghdad's southern district of Dura, hospital officials said.
And in the main northern city of Mosul, two civilians died and a policeman was hurt in a suicide bombing targeting a joint Iraqi-US patrol, police Major Mohammed Fathi said.
Meanwhile, the US forces on Saturday ended a major weeklong sweep dubbed operation "Matador" targeting insurgents loyal to Abu Musab al-Zarqawi.
Nine Marines were killed and 40 wounded in the operation in western Iraq near the Syrian border, while US forces killed more than 125 insurgents and detained 39 "of intelligence value", the US military said.
"During the seven day operation, Marines disrupted the known infiltration routes through the region and to deny safe havens," their statement said.
It notably aimed to prevent insurgents from obtaining weapons and foreign volunteers by way of Syria.
US forces "accomplished (their) mission and secured all objectives," the statement said, warning that US and Iraqi security forces would return to the area, some 300 kilometres north-west of Baghdad, in the future.
While much of the fighting was concentrated in the early stages of the operation, with US forces reporting the death of 70 insurgents in the first 24-hour period, the marines failed to secure all the towns in the region.
They appeared to have surrounded Al-Qaim, a town close to the border where insurgent activity was reported, but did not report capturing the city.
The US military reported mortar, machine gun and small arms fire in the town, but said this involved clashes between rival local groups.
It did not explain who the groups were.
According to local sources, fighting involved insurgents loyal to Zarqawi and members of the local Abu Mahal tribe.
Residents of Al-Qaim were reported to be hiding in their homes, while some families said they had fled into the nearby desert to escape the fighting.
Moreover, the interior ministry announced the arrest of several suspects, including four Palestinians, in connection with a suicide car bombing that killed 15 in central Baghdad on Thursday.
The arrests took place "nine hours after the attack", according to a ministry statement, which said, "the criminals clearly admitted their involvement in the attack".
In further unrest on Saturday, three Iraqi soldiers were shot dead when their position in Haswah, 80 kilometres south of Baghdad, came under attack.
North of the capital, gunmen killed an Iraqi civilian working as a translator with the US military in Samarra. The body of another Iraqi contractor shot several times in the head was discovered further south, security sources said.
Government sources said new rapid reaction teams of elite commandos would soon seek to flush out insurgents who have sought sanctuary on the outskirts of Baghdad.