More than 10 people have been killed in clashes between Arabs and Kurds in Kirkuk in the worst violence in Iraq's northern oil city since the war.
As officials prepared for city council elections this week, Arabs and Kurds fought over the weekend in mainly Arab districts in the southern part of the city, north of Baghdad.
Most of the fatalities occurred on Saturday but there was further violence yesterday. It was not clear what triggered the fighting but a senior US military official said members of each community blamed the other for the fighting.
"Both sides could be right. Some political language could be all you need as a catalyst," said Colonel William Mayville, commander of the 173rd Airborne Brigade.
"My sense is that there are external forces at work." Looting and violence among the city's mix of Arabs, Kurds, Turkmens and Assyrians first erupted after troops loyal to Saddam fled the city nearly six weeks ago.
Tension between majority Arabs and the Kurds has been partly driven by disputes over land or property seized under Saddam's 'Arabisation' campaign in the region. Many Kurds demand the right to return to homes from which they were expelled under Saddam.