Thousands of demonstrators on Friday also demanded that the Al Saud regime set free prominent Shia cleric Sheikh Nemr al-Nemr.
Sheikh Nemr was attacked, injured and arrested by Saudi security forces while driving from a farm to his house in Qatif on July 8.
Chanting slogans in support of social justice in the oil-rich Eastern Province, protestors asked the regime to stop killing civilians by the Saudi-backed forces in neighboring Bahrain.>/q>
Some of the demonstrators were also detained and some others were injured as a result of violent crackdown by the security forces, activists said.
Earlier in the week, similar demonstrations were held against the regime in the town of Awamiyah and the city of Buraydah.
Since February 2011, protesters have held demonstrations on an almost regular basis in Saudi Arabia, mainly in the Qatif region and Awamiyah in Eastern Province, calling 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 Al Saud regime, especially since November 2011, when Saudi security forces killed five protesters and injured many others in Eastern Province.
The Saudi Interior Ministry issued a statement on March 5, 2011, prohibiting “all forms of demonstrations, marches or protests, and calls for them.”
According to Human Rights Watch, the Saudi regime “routinely represses expression critical of the government.”