About 450 detainees held in US and Iraqi prisons were freed on Tuesday under an amnesty as part of a national reconciliation plan aimed at ending the bloodshed.
The move brings the number of those released so far this month to more than 2,500.
The sixth batch of detainees held at Abu Ghraib and other facilities run by the US military and Iraqis were assembled at the notorious US-run prison west of Baghdad before their release.
"Your release today is part of the prime minister's national reconciliation plan," Iraq's national security advisor Muwaffaq al-Rubaie told them.
"This is not a political game, it is a sincere attempt of reconciliation and to unite Iraq."
A US military spokesman in charge of detainee operations said all those released since Iraqi Prime Minister Nuri al-Maliki first spoke of a national reconciliation initiative on June 6 are suspected of being involved in the insurgency but have committed no violent crimes like bombing, killing, torture and kidnapping.
One of the items in Maliki's 24-point reconciliation programme presented to parliament on Sunday promises amnesty to detainees who have committed no crimes.