Saudi Arabia jails rights campaigner Abdulkarim al-Khader

Khader's colleagues Mohammed al-Qahtani (centre) and Mohammed Al-Hamid (right) were jailed in March

A founding member of Saudi Arabia's leading human rights organisation has been sentenced to eight years in jail on charges of inciting sedition.

Abdulkarim al-Khader had taken over as head of the Saudi Political and Civil Rights Association after two colleagues were jailed in March.

The association had also been disbanded as part of the March ruling.

The association was set up in 2009 by a group of lawyers and academics to reform the country's legal system.

Since then, it has been cracked down on by the authorities, with travel bans imposed on leading members of the association.

Five years of Khader's sentence are to be suspended providing he does not resume his activities on his release.

In March, association members Mohammed al-Qahtani and Mohammed al-Hamid were jailed, Qahtani for 10 years, while Hamid had an earlier sentence of six years upheld and a further five-year term added.

The had faced charges of setting up an illegal organisation and rebelling against the authority of the king.

The appearance in the past few years of human rights activists working out in the open in Saudi Arabia had seemed to herald a small change in the deeply conservative kingdom, the BBC's Sebastian Usher reports.

However, as murmurs of protest - especially from the Shia minority in eastern Saudi Arabia - began to be heard in the wake of the popular uprisings across the Middle East, activists came under attack, with accusations that they were encouraging sedition, he adds.

But where once he and his colleagues might have swiftly been forgotten, a media savvy generation of young Saudis are now using social networks to keep their cause alive, he says.