REPUBLIKA.CO.ID, NOIAKCHOTT -- A Mauritanian court has remanded in custody two men accused of keeping women and children as slaves, rights campaigners said Thursday, during a crackdown on the deeply rooted practice.

"The two (slave) masters were sent to prison," the SOS Esclaves (SOS Slaves) charity said in a statement, adding that the court hearing last week confirmed the existence of slavery, despite official denials.

The statement criticised an initial decision to release the men on bail, which was overturned by the appeals court on the grounds that it had impeded justice in a case involving crimes against humanity against two women and their children.

No more details on the allegations was available, but a judicial source confirmed that the hearing had taken place and a trial date was yet to be set.

Mauritania was the last country in the world to abolish slavery, in 1981, and since 2007 keeping slaves has been officially designated a crime, but the practice remains deeply entrenched, according to rights campaigners.

Earlier in December, the government ordered the creation of three special courts to try slavery cases.

The announcement followed the passing of a new law in August that declared it a "crime against humanity", criminalised a raft of new forms of slavery, such as forced marriage, and doubled maximum prison terms to 20 years.

A week later, however, a Mauritanian court upheld a two-year prison sentence against three anti-slavery activists who were arrested during a protest against the practice.

Slave status is often passed on from generation to generation, according to the Australia-based Walk Free Movement, which estimates that there are 156,000 slaves in Mauritania, around four percent of the population.

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