Saudi authorities regularly battle with al-Qaeda sympathisers

One policeman was killed and a seventh man arrested, the ministry said.

The group, cornered in the al-Nakhil district of the capital, was on the verge of launching attacks, according to officials quoted by al-Arabiya TV.

Saudi Arabia has seen a three-year campaign by militants, including an apparent suicide bomb attack on a major oil facility in February.

Several other members of the security forces were injured in the gun battle, officials said.

"The security forces at dawn Friday pursued seven members of the 'deviant minority' to a house in the al-Nakhil district of Riyadh, where they suddenly came under sustained automatic weapons fire," an interior ministry spokesman told the AFP news agency.

Internal struggle

February's attempted attack on the Abqaiq oil facility was the first physical attack on the kingdom's vastly important oil production facilities.

Previous attacks had focused on the compounds and facilities used by Western expatriates in Saudi Arabia.

Saudi authorities were slow to admit the country faced an internal struggle against militant Islamists, but that changed after bombings in May 2003 killed 35 people, says the BBC's security correspondent Frank Gardner.

Continual anti-terror operations have seen a string of militant leaders killed since then, but al-Qaeda sympathisers still appear active within the country.

The BBC may edit your comments and not all emails will be published. Your comments may be published on any BBC media worldwide.