Iraqi police captured and mistakenly released militant leader Abu Musab al-Zarqawi last year, the Iraqi deputy interior minister has said.
A 'wanted' poster for Zarqawi: there is a $25m bounty on his head
Maj Gen Hussein Kamal told reporters that Zarqawi was detained in the central Iraqi town of Falluja, but was released when nobody recognised him.
Falluja was the scene of a massive US-led operation in November 2004.
Zarqawi's group, al-Qaeda in Iraq, has claimed responsibility for many of the biggest attacks of the insurgency.
Gen Kamal said Iraqi police had detained Zarqawi for about three or four hours before releasing him.
"Iraqi police forces, who were in Falluja then, did not have sophisticated equipment to take pictures of him or take his fingerprints," he told the Associated Press.
But the deputy minister insisted Zarqawi would eventually be captured.
"He is human, he does not have the power of God," he said.
"He got away once, he will not get away the next time. He will be tried for the crimes he committed against the Iraqi people."
A British official has told the BBC's security correspondent, Frank Gardner, that there is no credibility to the claim that Zarqawi was detained.
Zarqawi is the most wanted suspect in Iraq and has a US bounty of $25m on his head.
His pictures and DNA have been supplied to both US and Iraqi forces.
The US military said it captured his driver at a checkpoint in western Iraq in February, but narrowly missed the main target.
In May, Iraqi Interior Minister Bayan Jabr said Zarqawi had been critically injured after a US air raid on his hideout in Qaim, on the Syrian border.
Following the attack, Zarqawi was said to have been treated at a hospital in Ramadi, fleeing 10 minutes before Iraqi and US force arrived.
The claim rapidly attracted postings on Islamist websites saying it was fraudulent.