Aimen Dean became an informant on al-Qaeda for British intelligence services in the late 90s.
The former spy believes that ISIS is not yet gone completely, as they will want to return for hidden cash in the cities of Mosul and Raqqa.
He said: “When the forces went into Mosul and Raqqa, they didn’t find the cash.
“No-one found the cash for ISIS.
“And ISIS cash is...