RIYADH, Saudi Arabia (AP) – Saudi security forces arrested 42 suspected terrorists, including four foreign nationals, allegedly involved in earlier attacks across the kingdom, the Interior Ministry said Saturday.

On Friday, Saudi security forces killed six suspected al-Qaida members and arrested a seventh following a shootout in the capital, Riyadh. One policeman was killed.

Saudi Arabia, a U.S. ally, launched an aggressive anti-terrorism campaign in May 2003 after suicide bombers linked to al-Qaida attacked three residential compounds in the capital, Riyadh.

Hundreds have been detained in the campaign, which has managed to capture or kill most of those named on the kingdom’s two most-wanted lists.

The 42 suspects are said to belong to a group inspired by “takfiri doctrine,” which maintains that those not adhering to its particular fundamentalist vision of Islam are considered “infidels.”

Saturday’s statement said 27 of the detainees were rounded up May 9-23 in Riyadh, Mecca.

Security detained an Iraqi and three Saudis in a June 17 raid on a desert camp in Hafer al-Baten.

Another nine – all Saudis – also were captured at a desert hideout in Hafer al-Baten, an official told The Associated Press on condition of anonymity, according to government policy. The official did not say when those nine were arrested.

Two more suspected were arrested after Friday’s raid.

Saturday’s statement named those killed in the raid – all suspected members of al-Qaida. None were on the latest most-wanted list issued by the kingdom in June 2005.

Saudi Arabia is the birthplace of Osama bin Laden.

AP-ES-06-24-06 1341EDT