BAGHDAD (Reuters) - Five Italian soldiers were wounded when their vehicle was hit by an improvised explosive device (IED) in the town of Makhmur in the northern Iraqi province of Nineveh, the military said on Thursday, adding that three were in serious condition.

The vehicle was carrying Italian special forces. The Italian national radio and television network "RAI" that the US helicopters took the wounded to a military hospital in Baghdad, where the surgery to amputate the leg of one of them.

The AFP news agency quoted a security source as saying that the attack took place in the town of Makhmour south of Mosul in the province of Nineveh.

"Our men were training Iraqi security forces to fight ISIS," Italian Foreign Minister Luigi Di Mayo said. "I am following the situation with regret and concern." The Rome prosecutor said it had opened an investigation into a "terrorist attack."

The attack comes three days before the 16th anniversary of an attack in the southern Iraqi city of Nasiriyah that killed 18 Italian soldiers, one Italian civilian and nine Iraqi civilians during the US-led foreign invasion.