Najim Laachraoui, one of the Brussels airport suicide bombers, has been identified by several Frenchmen held hostage by Islamic State in Syria as one of their prison guards, sources close to the investigation said, according to AFP.

According to one of the sources, four French journalists kidnapped in Syria in 2013 and 2014 had identified a guard known as "Abou Idriss."

One of these journalists, Nicolas Henin, "formally identified" Abou Idriss as Najim Laachraoui, said his lawyer Marie-Laure Ingouf, confirming reports in French newspapers.