Video of slaves apparently being auctioned in Libya is causing widespread outrage
But people undertaking the dangerous journey often drown in the Mediterranean Sea or are left stranded in transit countries where they face torture, rape and forced labour.
People-trafficking in Libya has provoked an emergency meeting of the UN Security Council.
The UN-backed government in Libya is promising to increase the number of flights repatriating stranded migrants, while Libya’s ambassador to the UN says slave auction reports will be fully investigated.
So, how can illegal migration be controlled in a failed state?