Ground Self-Defense Force personnel faced shelling by mortars and rockets while engaging in reconstruction and humanitarian efforts in Iraq about 10 years ago, a mission described by the unit chief as a "purely military operation," according to an internal GSDF report.

The report on the mission in Samawah from 2004 to 2006 could affect the Diet deliberations on the controversial security bills to expand the overseas role of the Self-Defense Forces.

Critics say that if the bills are passed, SDF personnel would come under greater risk. Under the war-renouncing Constitution, the SDF has never engaged in overseas combat.