Attacks by five suicide bombers on an Iraqi military base north of Baghdad on Sunday killed at least 15 members of the security forces and wounded 22 others, security sources said.
Two of the bombers detonated car bombs at the western gate of Camp Speicher, a former US base outside the city of Tikrit.
Three others blew themselves up after entering the section of the base where Iraqi police are being trained, police and military sources in the Salahuddin operations command said.
The Islamic State (IS), which controls swathes of territory in Iraq's north and west, claimed responsibility for the blasts in a statement distributed by supporters online.
The militant group said it targeted "trainers from the rejectionist army," a term used by the Sunni insurgents to describe Shiite Muslims.
Watch the VICE News dispatch Retaking Ramadi From the Islamic State: The Battle for Iraq:
Camp Speicher became a symbol of IS's brutality and hatred for Iraq's Shiite majority after as many as 1,700 soldiers from the base were killed in mid-2014 during the militants' lightning advance across the Syrian border.
Iraqi forces retook the center of the western city of Ramadi from IS last week, a victory that could help boost Prime Minister Haider al-Abadi, who has been rebuilding the military after a series of stunning defeats.
Iraq's Defense Ministry said IS has stepped up suicide blasts in response to setbacks in Ramadi. It said in a statement the group had used 22 bombers in two recent failed attacks in Anbar where Ramadi is located. The military responded, killing at least 42 militants including the bombers, the ministry said.
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