Defendants say they were tortured after protest over clearance of slum home to many of country's 'slave caste'
Thirteen anti-slavery activists in Mauritania were sentenced to between three and 15 years in prison on Thursday, despite criticism of the case against them by international rights groups.
A court in the capital Nouakchott found the 13 - all members of a group fighting hereditary slavery in the west African country - guilty of "use of violence".
But Amnesty International has said they were falsely accused because of their advocacy work.
The thirteen all claim they were tortured in prison in the run-up to the court case, and lawyers for the group have denounced Thursday's verdict as "a travesty of justice".
They were arrested between 30 June and 9 July after a protest by a Nouakchott slum community that was being forcibly relocated as the city prepared for an Arab League summit on 25 July.
The slum was home to many so-called Haratin - a "slave caste" under a hereditary system of servitude whose members are forced to work without pay as cattle herders and domestic servants, despite an official ban.
Biram Dah Abeid, a prominent Mauritanian former slave and anti-slavery campaigner who has run for the country's presidency, on Thursday denounced what he called the "shocking, blameworthy and complicit" silence of the African Union over the issue of slavery in the country.