Amnesty International has released a report criticizing European governments for supporting efforts by the Libyan Coast Guard to stop migrants crossing the Mediterranean and returning them to camps in Libya.

The report reveals how the EU's co-operation agreements with Libyan authorities responsible for grave human rights violations, including the Libyan Coast Guard and the General Directorate for Combating Illegal Migration, carry out search and rescue operations and prevent irregular departures.

Amnesty International says the policy has been successful with the number of arrivals in Italy fell by 67 percent since July of this year, but notes that the EU and Italian officials can't claim to be unaware of the grave violations being committed by detention officials and coast guard agents.

"Hundreds of thousands of refugees and migrants trapped in Libya are at the mercy of Libyan authorities, militias, armed groups and smugglers often working seamlessly together for financial gain," John Dalhuisen, Amnesty International's Europe Director, says in an interview with CNN.

"Tens of thousands are kept indefinitely in overcrowded detention centers where they are subjected to systematic abuse. European governments have not just been fully aware of these abuses; by actively supporting the Libyan authorities in stopping sea crossings and containing people in Libya, they are complicit in these abuses."

The report's findings are based on interviews with 72 refugees, asylum-seekers and migrants in Italy and Tunisia, as well as meetings with Libyan officials.

You can read the full report here.