Protestors have taken to the streets in the city of Katif for a second night, before a so-called “day of rage” against Saudi Arabia’s rulers planned for Friday.
There are reports of the police firing stun grenades and live bullets to disperse the crowd.
One minister there has warned that the government will “cut off any finger” raised against it.
The Saudi authorities place foreign journalists under tight restrictions but the BBC’s Paul Wood has sent this special report on whether the unrest in Libya and Egypt is spreading to Saudi Arabia.
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