Tens of thousands still being held in Syria, five years since the fall of ISIS

At its height, ISIS' self-declared caliphate spanned eastern Syria and western Iraq. Five years after its defeat by the US-led coalition, tens of thousands of suspected ISIS fighters and their families remain detained. An estimated 56,000 people, including 30,000 children, are held in at least 27 facilities and two camps — Al-Hol and Al-Roj — in Syria, according to Amnesty International.

CNN visited four detention camps and facilities: