Battle breaks out in Najaf

Najaf: Clashes broke out between Iraqi security forces and a group of Sunni insurgents who were hiding in orchards in the Shiite city of Najaf on Sunday.

There are reports that a helicopter came down during the fight but both Iraqi security forces and the US military have yet to release statements.

Reuters reports Governor Asaad Abu Gilel as saying that the militants, who included foreign fighters, had arrived in the city disguised as pilgrims in recent days and based themselves in the orchards, which he said had been bought three or four months ago by supporters of Saddam Hussain.

"There is a conspiracy to kill the clergy on the 10th day of Muharram," he said, referring to the day of the Muslim calendar on Monday. The climax of Ashura, it is the anniversary of the 7th century Battle of Kerbala which helped consolidate the schism between Shiite and Sunni Islam.

Abu Gilel said authorities had uncovered a plot by the fighters to kill some of the clerics on Monday, the climax of the Shiite mourning ritual of Ashura.

Iraqi forces had now surrounded the orchards and were battling the militants. No US troops were involved in the operation, but US helicopters were providing air support, he said. US forces largely withdrew from Najaf province last month. Gilel added that there were casualties but he could not say how many.