A Saudi court jailed a man for six years for organizing women’s demonstrations and taking part in protests against the regime, the official Saudi Press Agency reported on Wednesday.

The report gave no further details of the demonstrations over which the defendant was convicted.

The same Riyadh court sentenced another man to three years imprisonment for lese-majeste and incitement against the King, in material that defendant published on the internet about detainees in the conservative kingdom.

Protests and political organisations are banned in Saudi Arabia, where power is concentrated in the hands of the ruling al-Saud family.

Amnesty International on Wednesday called for the release of Waleed Abu al-Khair, head of the Saudi Arabia Monitor of Human Rights, saying he had been taken into custody without explanation after a court hearing on Tuesday.

Mr. Abu al-Khair had been accused of charges including inciting international organisations against the kingdom, London-based Amnesty International said.