The man convicted of murdering British aid worker Margaret Hassan has escaped from jail, Iraq's deputy justice minister has said.
Ali Lutfi Jassar, who had been reported missing last month, was jailed for life in June 2009 but had won the right to a retrial after an appeal.
Irish-born charity boss Mrs Hassan, 59, was abducted and shot dead in Baghdad in 2004. Her body has never been found.
Busho Ibrahim told the AFP news agency people had "facilitated" the escape.
The UK Foreign Office said it was "concerned" that Mr Jassar had reportedly escaped.
Mrs Hassan's sister, Deirdre Manchanda, said in July that the family had been told that Jassar could not be located in prison.
'Forced to sign'
Mrs Hassan, who had joint British, Irish and Iraqi nationality, had been married to an Iraqi and had lived in the country for 30 years.
She was director of charity Care International in Iraq when she was abducted in October 2004 on her way to work. She was shot weeks later.
Jassar was arrested by Iraqi and US forces in 2008 after contacting the British embassy in Baghdad and attempting to extort money in return for leading them to Mrs Hassan's body.
An English-speaking Sunni from Baghdad, he pleaded not guilty at the original trial.
He claimed he was forced to sign statements confessing to the charges after being beaten and given electrical shocks during questioning.
Mr Ibrahim's remarks were the first time Jassar's escape has been confirmed, with court officials having previously said only that he was missing.
Mr Ibrahim said: "This guy (Ali Lutfi Jassar), he escaped from prison.
"People facilitated his escape, he is gone."
The AFP reported that Jassar escaped from Baghdad Central Prison, on the site of the former Abu Ghraib prison, during riots in September 2009.
The deputy justice minister added that he first discovered that Jassar had escaped about "20 or 30 days ago".
He said: "At that time, he seized the opportunity of the riots in the prison in September 2009 and he escaped. He was the only one who escaped."
He also said that people suspected of helping Jassar to escape had been arrested and were going to appear in court, but gave no further details, the agency reported.
Mr Ibrahim's comments come the same day that Jassar's retrial at Baghdad Central Criminal Court was adjourned until 19 September, AFP reported.
In a statement, the UK Foreign Office said: "We are very concerned by reports that Ali Lutfi Jassar has escaped from the Iraqi prison system.
"We continue to raise this issue with the Iraqi government and to work closely with the Hassan family and their lawyers in Baghdad.
"Justice must be done for this dreadful crime, committed against someone who dedicated her life to helping all Iraqis. "