Chanting anti-Al Saud slogans, the protesters called for the release of prominent Shia cleric Nemr al-Nemr, who was injured and detained in the city in July, while on his way back home.
Al-Nemr’s arrest sparked massive protests, with angry demonstrators demanding his immediate release.
The Shia cleric has been severely tortured by Saudi security forces in jail.
The Saudi protesters also expressed solidarity with anti-regime protesters in Bahrain, who have been brutally suppressed by the Saudi-backed forces of the Persian Gulf island state.
Since February 2011, protesters have held demonstrations on an almost regular basis in Saudi Arabia, mainly in Qatif and Awamiyah in Eastern Province, primarily calling for the release of all political prisoners, freedom of expression and assembly, as well as 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 province.
Similar demonstrations have also been held in Riyadh and the holy city of Medina over the past few weeks.
According to Human Rights Watch, the Saudi regime “routinely represses expression critical of the government.”