Saudi Arabian security forces have exchanged fire with fighters responsible for a deadly wave of unrest in the kingdom over the past two years.

The clashes took place on Sunday in the city of al-Rass in the al-Qassim region, 355km northwest of the capital, Riyadh, after security forces surrounded several wanted men in a neighbourhood called al-Jawazat, a security official said.

"Saudi security forces raided a house in al-Rass where suspected members of the deviant group are believed to be hiding," the source said.

There was no immediate word on casualties, but witnesses said ambulances were seen carrying injured people. It was unclear if they were troops, dissidents or bystanders.

The incident came less than a month after a suspected al-Qaida member was arrested along with two of his companions, after a heavy gun battle on 13 March in the Red Sea city of Jedda.

Violence blamed on al-Qaida since May 2003 has killed 90 civilians, according to official figures. Thirty-nine members of the security forces and 92 fighters have also been killed.

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