In Ramadi, US tanks and helicopters killed 10 Iraqi civilians when they opened fire on a residential district, a doctor said.
Abd Al-Salam Muhammad of Ramadi Hospital said a further 40 Iraqis were wounded by US forces in the town, west of Baghad.
Witnesses said US forces had clashed with Iraqi fighters in the town earlier on Sunday.
A US military spokesman did not immediately have any information on the fighting.
Earlier in the day, at least 10 Iraqis were killed and 35 others injured after US helicopters fired missiles at a crowd in a central Baghdad street.
The missile attack, which also killed a Palestinian journalist, followed fierce clashes which began when US military vehicles, firing stun grenades, entered the city centre at about 1100 GMT on Sunday, an Iraqi journalist told Aljazeera.
Heavy clashes were reported in
Twenty-eight year old Palestinian television journalist, Mazin al-Tumaisi, was killed and two photographers wounded when the US missiles struck.
Al-Tumaisi, who worked for Saudi television Akhbariya and as a fixer for the Arab satellite channel al-Arabiya, was killed covering the fighting in Haifa Street, said Al-Arabiya reporter Ahmad Salih.
An Iraqi cameraman working for Reuters and an Iraqi photographer working for Getty Images were also wounded slightly by flying shrapnel, said a source at the London-based news agency.
In other unrest, three Polish soldiers were killed and three others wounded on Sunday in an attack near the central Iraqi city of Hilla, a spokesman for the Polish military said.
At least two Iraqi Civil Guard officers were killed when armed assailants attacked a convoy bringing foreigners from Baghdad airport to the city centre.
Iraqi fighters say they have shot
Several vehicles in the convoy caught fire during the attack which occurred on a highway overpass in the Yarmuk neighbourhood.
Three other members of the guard were killed and seven others injured in Jibla city north of Hilla in central Iraq when an explosive device targeting their patrol detonated on Sunday, according to Aljazeera.
Meanwhile, three Iraqi policemen were killed and four others injured after the driver of a vehicle they were pursuing blew himself up.
The explosion took place on a road near the main highway in Amiriya, west of Baghdad.
An Iraqi journalist told Aljazeera Iraqi police explained that as the patrol approached the vehicle, the driver blew himself up.
Elsewhere in the Iraqi city of Falluja, armed fighters claimed to have shot down an unmanned US Marines reconnaisance aircraft.
Unmanned aircraft – also called drones or Remote Piloted Vehicles (RPVs) – are used by the US army to relay video surveillance of enemy positions to commanders.