The Saudi authorities have accused a "foreign country" of trying to undermine stability in the kingdom after 14 people were reported injured in clashes between police and protesters in the country's predominantly Shia Muslim-populated east.
Saudi Arabia has confirmed that 11 security personnel and three civilians were injured in fighting in the eastern city of al-Qatif early on Monday. Other reports say 24 men and three women were wounded as police opened fire at protesters, The Independent newspaper said.
Analysts have interpreted the "foreign country" as a veiled reference to Saudi Arabia's regional rival, Shia-ruled Iran.
The unrest reportedly began on Sunday in the Shia town of al-Awamiyah, when Saudi police arrested a 60-year-old man to force his son - an activist - to give himself up, the report said. The authorities said the violence broke out when police clashed with assailants who used automatic weapons and Molotov cocktails, Bloomberg said, quoting a Riyadh-based news service.
Saudi Arabia, the world's largest oil supplier, has avoided the large-scale popular protests that toppled the leaders of Egypt and Tunisia earlier this year and continue in Syria, but small protests were seen in the country's Shia-populated Eastern Province, including Awwamiya and al-Qatif.
Saudi Arabia's Shia minority, who make up 10 percent of the kingdom's 23-million population, have long complained of discrimination against them by the fundamentalist Sunni Saudi authorities.