An overnight US air strike on Falluja killed at least 18 people, including three children, and left about nine wounded, Aljazeera has learnt.
And two Iraqis more were killed and 11 wounded when armed clashes erupted in Sinai quarter east of the city on Thursday morning, sources told Aljazeera.
Two houses were destroyed late on Wednesday when a US fighter jet fired two missiles at the town's residential district of Jabal, some 65km west of Baghdad.
A local journalist, Abu Bakr al-Dulaimi, said the blasts were so powerful that "bodies were scattered and thrown away about 50 metres from the place of the explosion.
"The US forces always allege that they have targeted houses used by Abu Musab al-Zaqawi while the Fallujans, many times, have denied such allegations, which are groundless and false.
"Most casualties were old men and women and children", al-Dulaimi said.
Saif al-Din Taha of the Falluja general hospital told Aljazeera that all the overnight wounded were ordinary civilian families.
Confirming that children are amongst the dead, he said it was difficult to identify the corpses as "the bodies are torn to pieces".
But US-led forces insisted the overnight strike targeted a safehouse used by followers of alleged al-Qaida leader Abu Musab al-Zarqawi.
"The strike, based on multiple intelligence sources, targeted two buildings used as safehouse and meeting points for al-Zarqawi associates who had executed someone on Wednesday," the US military claimed.
"The al-Zarqawi associates were observed removing a man from the trunk of a car, executing him then burying his body," the military said.
The latest air strike comes after US forces pounded the town on Saturday, killing five people and wounding 42 others.
US-led forces have targeted Falluja both from the land and air frequently in the past and laid a three-week siege of the town in April in a vain attempt to quell Iraqi opposition to their presence.