The chair of the AU commission Moussa Faki Mahmat said that between there was no way of knowing exactly how many black Africans were stranded in Libya trying to get to Europe.
Many of them are held in illegal detention centres by human trafficking gangs.
Earlier this week African and European leaders agreed with the United Nations to set up, what they are calling, a joint task force to dismantle the camps.
The French president Emmanuel Macron had suggested that the force would include policing and military capacities; a suggestion now widely rejected by both the AU and the EU.
On one point, leaders at the summit were in agreement.
‘Deplorable’, ‘inhumane, ‘barbaric’ were their reactions to the CNN investigation into African migrants, being sold as slaves in Libya.
The Nigerian president Muhammadu Buhari said they could not stand by while his countrymen and fellow Africans were being sold like ‘goats’.
The joint task force is charged with ‘freeing the detainees’ and repatriating them on a voluntary basis to their home countries.
The Moroccan King Mohamed IV has said he will supply the flights to move them.
Earlier this week the AU sent a fact finding mission to Libya – and the facts are grim.
Amira Elfadimirl, the AU Commissioner for Social Affrairs visited a camp in a government controlled area where 4000 men women and children were being held against their will.
She told RFI she believed the crisis sparked by slave auctions ‘would spur the international community into action’.
Tripoli believes there are 42 more similar camps in areas it controls. No one knows how many are in rebel held areas.
The scale of such an operation would be huge. The Libyan government has said its forces will help free people in areas it controls. Analysts say it has the military capability to do so.
Nevertheless questions remain for people detained in rebel areas. It is unlikely that the rebels would release them voluntarily.
And, contrary to what president Macron said, there is no appetite to see foreign boots on Libyan soil any time soon.