The United Nations refugee agency say 800 migrants died when a boat capsized in the Mediterranean at the weekend after speaking to survivors.
The captain and a crew member have been arrested and charged with people trafficking.
The captain also faces a charge of reckless multiple homicide in relation to the disaster off the coast on Libya.
It comes after EU ministers announced measures to help stop the crisis in the Mediterranean - including a proposal to double the size of its search and rescue operations.
John Dalhuisen - Director for Europe and Central Asia at Amnesty International - says depending on where crews are based it could make all the difference.
