Behind Bars: Worlds Toughest Prisons

Urso-Branco - the White Bear - is one of the most notorious prisons in Brazil. In the past 20 years more than 100 people have died in riots. (S3 Ep3)

Colony 8 in Ukraine is one of the toughest and most notorious prisons in the country. It is said that no one has ever escaped from here.

A high-security prison covering an area the size of ten football pitches. Surrounded by six-metre-high walls, and the sea, the facility houses up to 800 criminals under the strictest security measu...