The firefight in the town of Yusifiyah also left one army officer dead, the statement said, adding that two heavy machineguns, 15 rifles and five grenade launchers were seized, along with other equipment.
"Iraqi security forces confronted a failed attempt by Daash gang members to break into a military camp," the statement said, referring to the Arabic abbreviation for the powerful Islamic State of Iraq and the Levant jihadist group.
"The security forces ... Killed more than 40 terrorist attackers, and the attack resulted in the death of one of our officers when he was confronting these criminal gangs."