LONDON

A Guantanamo Bay prisoner turned suicide bomber scored a $1.6-million payout for his ordeal - then turned to terror.

The news has triggered howls of outrage in the UK media with pundits asking how he slipped through the cracks.

ISIS terrorist Jamal Al-Harith - formerly Ronald Fiddler - blew himself to smithereens during an attack on an Iraqi army base this week.

“Plainly he was a terrorist and he was a potentially dangerous terrorist,” Alex Carlile, Britain’s former independent reviewer of terrorism legislation, told the BBC.

“The issue was the legal disclosure rules. If someone brings a civil action for damages they are entitled to disclosure of material, some of which may be national security material.”

Telling a tale of woe, Al-Harith was one of 16 men paid $13.4 million in compensation in 2010 after the British government settled a lawsuit claiming its spies were complicit in the torture of prisoners at Gitmo.

According to the Daily Mail, al-Harith used his taxpayer-funded bounty to buy a £220,000 semi-detached home in Manchester and found work as a web designer.

He married, set up a computer business and worked at an Islamic school.

But in 2014, the old demons came calling and al-Harith travelled to ISIS-controlled Syria. His British wife, Shukee Begum, followed and tried to bring her husband home.

Al-Harith’s jihadi journey began when he converted to Islam and ventured on a religious pilgrimage to Pakistan in October 2001.

The UK Sun reports that he called his family after being captured by the Taliban claiming he desperately wanted to come home. Instead, he was captured by the Americans and sent to Gitmo.

After heavy lobbying, he was released in March 2004 and received his payout in 2010. His brother, Leon Jameson, said when he saw the picture of the suicide bomber embarking on his mission, he knew it was his brother.

“It is him, I can tell by his smile,” Jameson told The Times. “If it is true then I’ve lost a brother, so another family (member) gone.”

Jameson added that his brother had “wasted his life.”

The country’s Labour party and former Prime Minister Tony Blair have been blistered by the Tories and the Liberal Democrats over their handling of the affair. Labour swore none of those released from the prison on the tip of Cuba posed any threat.

“Fiddler is part of a considerable cadre of people released from Guantanamo Bay who have returned straight to the ranks,” security expert Kyle Orton told the Mail. “This keeps happening so the drive to shut the camp has always been a very, very serious threat.”

He added: “Allowing people to be put back in the field is a concrete security threat. The drive to release has been disastrous in terms of the consequences for Western security.”