A British suicide bomber who blew himself up in Iraq was identified as a former Guantanamo Bay detainee, prompting questions about how his case was handled after lawmakers and the media lobbied hard for his release.

Jamal al-Harith is said to have detonated a bomb this week at an army base near Mosul.

The Islamic State identified the 50-year-old bomber as Abu Zakariya al-Britani, a Muslim convert from Manchester. He was born Ronald Fiddler and was known more widely in Britain as Jamal al-Harith. He was also identified by his brother, Leon Jameson, who told the Times of London that the photo released by the Islamic State of a man in an explosives-laden car was his younger brother. He “wasted his life,” Jameson said.

In March 2004, after a massive campaign by politicians and the media, Harith was released from the U.S. base at Guantanamo Bay along with four others who had been held for two years without trial.

He received a reported 1 million pounds in compensation in 2010 after the British government settled a lawsuit alleging that British agents were complicit in his torture.

The Islamic State identified Abu Zakariya al-Britani as the suicide bomber who attacked a military base in Iraq. Known more widely as Jamal al-Harith, he was released from Guantanamo Bay in 2004. (Remy De La Mauviniere/Associated Press)

Born in Manchester, Harith was a Web designer who converted to Islam in college, where he studied computing and religious studies. Shortly after the 2001 terrorist attacks in New York and Washington, he was kidnapped when crossing the Pakistan-Afghanistan border and handed over to the Taliban, who accused him of being a British spy. According to his Guantanamo prisoner file, published by WikiLeaks, he was later transferred to U.S. forces’ custody and taken to Guantanamo a few months later because he was “expected to have knowledge of Taliban treatment of prisoners and interrogation tactics.” The file also said he traveled to Sudan in 1992 with “Abu Bakr, a well-known al-Qaeda operative.”

He reportedly struggled to find work when he returned to the United Kingdom, and in 2014, he traveled to Syria to join the Islamic State. Shortly after he left, his wife, Shukee Begum followed him to Syria with her five young children in an attempt to persuade him to come home. She described her time in the so-called caliphate as “not my cup of tea.

Questions have been raised about how he slipped through the surveillance net and whether it was right for the British government to campaign for his release and then pay him compensation.

Arthur Snell, the former head of Prevent, the government’s flagship counterextremism program, said that British authorities had failed to keep tabs on Harith.

Speaking to the BBC, he said: “It's obvious that collectively the authorities — and obviously I have some personal responsibility there — we failed to be aware of what Fiddler was up to.”

The Daily Mail, a British tabloid, took a swipe at Tony Blair, who was prime minister when Harith was released from the prison camp in Cuba.

“Still Think He Wasn’t A Danger, Mr Blair? Fury at Labour government’s £1m compensation for innocent Brit,”a headline said.

In a strongly worded statement, Blair called the Mail’s coverage “utter hypocrisy.”

“It is correct that Jamal al-Harith was released from Guantanamo Bay at the request of the British Government in 2004,” he wrote. “This followed a Parliamentary and massive media campaign, led by the Daily Mail, the very paper that is now supposedly so outraged at his release and strongly supported by the then Conservative Opposition. The Mail headline shortly after he was released after months of their campaigning was ‘Freedom At Last for Guantanamo Britons.’ ”

Jack Straw, a Labour politician who served as foreign secretary under Blair, told the BBC that he did not think the Blair administration had made a mistake.

“I don’t think I did get it wrong,” Straw said. “It’s got to be acceptable, we have to be grown-up about this, that if you are asking ministers to release people. . . sometimes they may carry on with criminal activities.”