People in Taif in the southwest of the country demonstrated on Thursday to express solidarity with political prisoners.
The peaceful protesters also demanded an end to rights violations in the monarchy.
US-backed Saudi Arabia regime has arrested scores of anti-government protesters since the beginning of the uprising in the country. Prominent cleric Sheikh Nemr Baqir al-Nemr is among the detainees.
Sheikh Nemr was injured and arrested by Saudi security forces of the Al-Saud regime while driving from a farm to his house in Qatif on July 8.
Since February 2011, protesters have held demonstrations on an almost regular basis in the Kingdom’s east, mainly in Qatif and Awamiyah.
The demonstrators called for the release of all political prisoners, freedom of expression and assembly, and an end to widespread discrimination.
However, the demonstrations have turned into protests against the repressive Al Saud regime, especially since November 2011, when Saudi security forces killed five protesters and injured many others in the oil-rich region.