The forces surrounded several houses in al-Jamima Township in al-Awamia which is located in al-Qatif region, and started firing at people in the streets.
A young man was killed in the attack and 15 people were wounded among which seven were reported to be in critical condition.
One house was also burned down in this attack.
Saudi Arabia has been facing social protests since 2011, influenced by the Arab Spring that started with 2011 Tunisian revolution.
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.
Anti-government protests have intensified since November 2011, when security forces opened fire on protestors in Qatif, killing five people and leaving scores more injured.
Activists say there are over 40,000 prisoners of conscience in Saudi Arabia, many of them being held without trial or charges.
According to Human Rights Watch, the Saudi regime “routinely represses expression critical of the government.”
SHI/SHI