The newspaper said in a released statement, "There is now sufficient evidence to suggest that these pictures are fakes and that the Daily Mirror has been the subject of a calculated and malicious hoax."
"The Daily Mirror therefore apologizes unreservedly for publishing the pictures and deeply regrets the reputational damage done to the QLR and the Army in Iraq."
The photos, depicting British troops urinating on prisoners and beating and abusing detainees, caused an uproar when they were first published on the front page of the anti-war paper. But the authenticity of the pictures was immediately questioned, and troops from the QLR denied the photographs were real.
"It wasn't a British soldier degrading an Iraqi," said QLR commander Brigadier Geoff Sheldon. "It was a mocked-up fake, not even taken in Iraq."
As a growing number of experts questioned the veracity of the photos, Morgan remained defiant, defending the decision to publish the photos and saying he would not resign.
"The pictures accurately illustrated the reality about the appalling conduct of some British troops," he said.
Morgan's stance angered many, saying the decision to publish the inflammatory and untrue pictures put lives in danger.
"The photos that were published in the Daily Mirror have done great damage to the reputation of our troops, who are serving under some of the most difficult conditions in Iraq," said Conservative Party deputy leader and foreign affairs spokesman Michael Ancram.
The Mirror was not the only newspaper rocked by fake photos purportedly from Iraq. On Wednesday the Boston Globe published graphic photos of alleged sexual abuse of Iraqi women by U.S. soldiers. The suspect photos were later found to have been taken from a hardcore pornography Web site.
"This photo should not have appeared in the Globe," said editor Martin Baron. "First, images portrayed in the photo were overly graphic. Second, as the story clearly pointed out, those images were never authenticated as photos of prisoner abuse. There was a lapse in judgment and procedures, and we apologize for it."
The photos were taken by the Globe at a Tuesday press conference held by Boston City Councilor Chuck Turner, who in turn said he had gotten them from "a very legitimate person."
Although the reporter who wrote the accompanying story, Donovan Slack, expressed doubts about the veracity of the photos, a number of editors at the Globe approved the publication.
"It's insane," Slack said. "Can you imagine getting this with your cup of coffee in the morning? Somehow it got through all our checks. Our publisher's not having a very good day today."