A makeshift boat is heading for Europe. On board, 126 people including eight children. Most of the passengers are Sudanese. They fled Libya where they were locked up in detention centers.

Many think they are saved by an NGO. But they were Libyan coast guards who intercepted their boat. They bring them back to Tripoli.

The weakest migrants are taken care of by the International Organization for Migration (IOM) but all the others return to detention centers. NGOs regularly denounce the living conditions of migrants in these centers. They lack food and are victims of violence and sometimes even torture.

"We get hit, we do anything, it's been three months since I was in prison, if you eat, if you do not eat, if you die, that's not their problem!", Says one young Chadian.

Exclusive report by Julie Dungelhoeff, Catherine Norris Trent and Abdallah Malkawi.

See also, the first episodes of our series of reports:

>> Battle of Tripoli: Libyan civilians living in fear of bombing

>> In the midst of fighting for Tripoli with a Misrata militia