A tribunal in Mauritania has sentenced 13 anti-slavery activists to up to 15 years in prison for their role in a riot in June in a decision condemned on Friday by international campaigners as a "devastating blow."
The West African nation is a focus of activism by the modern anti-slavery movement over a practice believed to affect between four and 20 percent of the population.
Authorities arrested the 13 members of the Initiative for the Resurgence of the Abolitionist Movement (IRA) in late June and early July after a protest against eviction by residents of a slum in the capital Nouakchott, many of whom are themselves former slaves.
Several police officers were injured in the demonstration.
"The sentences are a devastating blow to the Mauritanian anti-slavery movement," said Sarah Mathewson, Africa Program Manager at Anti-Slavery International. "The activists are clearly being targeted by the government for their work to expose and denounce slavery, still commonplace in the country."
A tribunal found the defendants guilty on Thursday of counts including attacks against the government, armed assembly and membership of an unrecognized organization.
The defendants said they were not present at the June protests and that the trial was a politically-motivated attempt by the government to discredit their organization. IRA vice president Brahim Ramdane called the verdicts a "parody of justice" and said the group's lawyers were deciding how to respond.
Mauritania has attempted to crack down on slavery and last year passed a law making it a crime against humanity and doubling prison terms for offenders. Campaigners say it will not be enough to stamp out the practice.
Other anti-slavery campaigners, including those in the IRA, have also faced stiff sentences. IRA head Birame Ould Abeid has been jailed several times. He also came a distant second in a 2014 presidential election.