Iraqi forces have attacked a camp housing an Iranian exile group north of Baghdad, home to about 3,500 people.
Reports suggest at least three died in the clashes between troops and the People’s Mujahideen Organisation of Iran (PMOI) at Camp Ashraf.
The PMOI said more than 25 were killed and many wounded in the raid, but Iraqi officials have disputed the figures.
US Defence Secretary Robert Gates expressed concern and urged Iraq to show restraint.
The PMOI, a guerrilla group that opposes Iran’s Shia cleric leaders, is considered a terrorist group by the US and Iran.
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