Salman Abedi, the Manchester attacker, travelled between the UK and Libya where he was under surveillance by local authorities. Yet Abedi easily returned to Britain, where he built and detonated a bomb.
Manchester is home to the UK's largest Libyan community which included Salman Abedi, who killed 22 people in a terror attack in the city centre on the night of May 22.
Abedi travelled to Libya with his brother on the same date before returning to Britain before the attack. His brother, who has been detained by Libyan authorities, says both of them joined Daesh. But these are details are still painting a very scant picture about why, ostensibly, the Manchester-born young man decided to die for the terror group, or if his trip to Libya played a compelling part.
In 2011, many Britons of Libyan descent went to Libya to fight in the revolution.
For years experts have warned about blowback and questioned why Britain turned a blind eye towards its teenagers to a war zone.
One former fighter who travelled to Libya during the revolution looks back at how young people like him were compelled to go to the front lines and how easy it was to get away with going to Libya.
TRT World's Sara Firth sat down with him.