Baghdad - Three Iraqi civilians were killed on Sunday and another three soldiers were injured in two separate incidents in Iraq's restive Diyala province, a security source said.

Some gunmen, suspected to be affiliated to the al-Qaeda terrorist network, attacked a gathering of people in Baquba, shooting three civilians dead, a security source told the Voices of Iraq (VOI) news agency.

Also in Diyala, three Iraqi soldiers were injured in a blast that targeted their army patrol in Baquba's Beldouzer district.

Baquba is located 57 kilometres north-east of the Iraqi capital of Baghdad.

In a similar incident, another three Iraqi soldiers were injured in an explosion that struck their patrol in west Baghdad.

The US forces announced Sunday morning the death of one of its soldiers when a vehicle rolled over to the south-east of Baghdad.

The soldier's death brings the number of US troops who died in September to 23. In August, some 23 US soldiers died. (dpa)