A suspected associate of British ISIS leader Jihadi John has been held by authorities in Turkey.
Aine Davis, originally from Hammersmith, is thought to have operated as a guard at an ISIS prison holding foreign hostages in Syria.
He was also the jihadi at the centre of a sensational court trial last year which saw his wife, Amal el-Wahabi, jailed for funding terrorism while university student Nawal Msaad, 27, was sensationally cleared of trying to smuggle £16,000 in her underwear to Syria.
Aine Davis, (left) originally from Hammersmith, poses with weapons in Syria
The court case revealed how Aine Davis had a controlling presence over his wife, Amal el-Wahabi, who was convicted of helping to fundraise his life in Syria.
Prior to travelling to Syria, Davis was convicted six times for possessing cannabis and was also heavily involved in gang circles, where he was known as 'Biggz.'
The gangster worked as a gun runner, selling handguns before the weapons factory he worked for was busted by police.
It is unclear when Davis converted to Islam and adopted the name Hamza. When police raided his wife's home, Davis's ipod revealed he used to listen to lectures by radical American cleric Anwar al-Awlaki.
He met his wife Amal el-Wahabi at Westbourne Park mosque in 2006 and despite the disapproval of her parents, they developed a close relationship.
Davis' new found interest in religion led him to persuade his girlfriend that they should move to Yemen.
Wearing a tactical vest and clutching a rifle, Aine Davis (kneeling second from right) looks at ease in Syria
Davis enrolled at a madrassa to study Arabic and the Qur'an, only for the couple to return to the UK when Amal became pregnant.
The relationship fell apart just two months before their first child was born in 2009. Davis embarked on several trips to the Middle East, visiting Saudi Arabia, Egypt and returned briefly to Yemen.
Two years later, Davis and el-Wahabi restarted their relationship for a second time and by May 2013, the couple had their second child.
Despite the new birth, Davis left el-Wahabi two months later, travelling first to Turkey before crossing into Syria and joining ISIS.
The Turkish officials declined to give further details, saying investigations by the police and intelligence agencies were continuing.
The news of Davis's arrest in Istanbul comes as British Prime Minister David Cameron said he could not yet confirm the death of Mohammed Emwazi, who was dubbed Jihadi John after appearing in videos showing the killings of U.S. and British hostages.
The Pentagon said it was still assessing the effectiveness of Thursday's strike.
But a U.S. official said the attack in the northern Syrian town of Raqqa, Islamic State's de facto capital, had probably killed Emwazi.
The Syrian Observatory for Human Rights, a Britain-based monitoring group, quoted sources in Raqqa as saying Emwazi had been blown to pieces.
Former hostages of Islamic State have suggested the group of British Islamists was assigned to guard foreign prisoners. In the British media they were nicknamed John, Paul and Ringo, after members of the Beatles, because of their English accents.
Emwazi took part in videos showing the murders of U.S., British and other hostages. Dressed entirely in black, a balaclava covering all but his eyes and the bridge of his nose, he became a menacing symbol of Islamic State brutality and one of the world's most wanted men.