US forces have renewed heavy air and artillery strikes on the rebel-held Iraqi city of Falluja this evening.
Iraqi insurgents responded with fierce mortar and rocket-propelled grenade attacks against US positions on the edge of the city.
Last night, US planes and tanks killed five people in their bombardment of Fallujah.
The US military said two air raids after midnight destroyed "fighting barricades" prepared by insurgents in the northeast and southeast of the Sunni Muslim city.
The strikes followed what witnesses said was an intense late-night bombardment of eastern and northwestern districts by AC-130 aircraft and tanks that shook the city for half an hour. They said the bombardment was the heaviest on the city for several weeks.
A hospital doctor said five people had been killed, including a woman and child. All had been in a car hit while trying to escape the city. A woman was badly wounded and a teenage girl lost a leg in earlier air strikes, officials said.
The US military is poised for an assault on Fallujah, some 30 miles west of Baghdad, and the Sunni city of Ramadi further west, as part of the interim government's drive to pacify Iraq before national elections planned for January.
US marines were apparently staying at the edge of the city, most of whose 300,000 people have already fled for safety.
Interim Prime Minister Iyad Allawi, now visiting Europe, has not publicly given the go-ahead for the storming of Fallujah and Ramadi, but the Marines say they only need the order from him and newly re-elected President George W. Bush.
A car bomb blew up this morning in the town of Iskandariya, some 32 miles south of Baghdad, an Interior Ministry spokesman said. He had no immediate word on casualties.
Shias in the slums of Sadr City, where anti-American cleric Moqtada al-Sadr has a strong following, said Mr Bush must now keep his pledges to rebuild Iraq and hold elections.
Sadr, whose militia staged two uprisings this year, has recently moved towards joining the political process, ordering his Mehdi Army fighters to hand in their weapons in Sadr City.