Four people have been injured in an attack by Saudi security forces in the town of Awamiyah in Eastern Province.
Security forces also reportedly used live ammunition during the attack on Tuesday.
The hospital where the injured are being treated has been surrounded by security forces.
Since March, Saudi Arabia, mainly the restive Eastern Province, has witnessed demonstrations that call for political and social reforms, the release of people detained without charge or trial, and the right to peaceful protest on the streets.
Amnesty International says Saudi authorities have repressed the demonstrations “in the name of security.”
On December 16, dozens of men and women were arrested at the Rajihi mosque in Riyadh during a peaceful demonstration to call for the release of relatives who have been detained without any charge or trial “for several years.”
Amnesty called on Saudi authorities on December 22 to “immediately and unconditionally” release those detained at the Rajihi mosque “solely for peacefully exercising their right to freedom of expression and assembly.”
In November, security forces killed five protesters and injured many others in Eastern Province. The funerals for the victims usually turned to demonstrations with protesters chanting slogans against the Al Saud regime.
Thousands of people have been detained in Saudi Arabia on security grounds over the past decade. Those who have been charged with security-related offences and brought to trial have faced “grossly unfair and in many instances secret proceedings,” according to Amnesty.