Saudi forces kill suspected militants after siege

RIYADH, Feb 27 (Reuters) - Saudi forces on Monday killed about five suspected militants believed to be linked to an al Qaeda attack on a major oil facility, security sources said.

A firefight ensued at dawn after security forces besieged the men, who were hiding in a villa in the affluent al-Hamra district of east Riyadh where several Western residential compounds are located.

Witnesses said they heard the sound of heavy gunfire and what appeared to be mortars as security forces surrounded the area and sealed it off before dawn.

The shoot-out ended after two hours with the deaths of all of the men inside the building, believed to number about five, the security sources said.

One source said the men were traced partly through Internet surveillance. An Internet statement was issued at the weekend claiming that al Qaeda was behind an attack on the world's largest oil processing plant in Abqaiq on Friday.

The attempt to storm the site in east Saudi Arabia near the Gulf coast was the first direct strike on a Saudi energy target since the militant group launched attacks aimed at toppling the U.S.-allied monarchy in 2003.

It was also the first major attack by militants opposed to the Saudi monarchy since suicide bombers tried to storm the Interior Ministry in Riyadh in December 2004.

Authorities say two of the bombers were on a list of top wanted al Qaeda-linked Islamic militants issued last year. Al Qaeda had previously identified them in an Internet statement posted on Saturday and vowed more attacks.