Three assailants in a car sprayed bullets at the soldiers who were guarding a checkpoint at the entrance of a palace formerly used by Saddam Hussein, a police officer told AFP, requesting anonymity.

"The three soldiers were killed and a fourth was wounded," the policeman said, adding that the gunmen sped away from the scene.

Coroner Ahmed Abdullah Rajaf confirmed the death toll at the hospital in Mosul, 370 kilometres (230 miles) north of Baghdad.

The former Iraqi army, once 350,000-strong, was dissolved last May by US civilian administrator Paul Bremer.

Since then three US-trained battalions have been formed to replace it, as part of coalition plans to stand up a 27-battalion army numbering some 40,000 soldiers by the end of the year.

WAR.WIRE