Employees at a Swedish-Swiss oil facility in Saudi Arabia where armed militants killed five Westerners Saturday have decided to leave the country. In the meantime, the kingdom's crown prince is vowing to stamp out terrorism, no matter how long it takes.

While the U.S. consul's office in Saudi Arabia is urging Americans to leave the kingdom, all Swedish employees of the oil services company ABB in the Saudi Arabian port of Yanbu are leaving.

The exodus follows Saturday's shooting spree by four armed militants that left at least five Westerners and a Saudi security man dead. Several other people were wounded in the attack.

The dead engineers were two Americans, two British, and an Australian. They worked for the energy company at the port of Yanbu in northwestern Saudi Arabia.

The Saudi interior ministry says the militants sprayed gunfire inside the oil contractor's office and then became involved in a car chase with Saudi police. The four gunmen were later shot and killed.

Saudi authorities said three of the attackers worked at the complex where the shooting took place. They said the attackers used their card keys to get into the facility and then walked into the offices, randomly shooting at employees. One of the attackers was reportedly on the kingdom's list of most wanted terrorists.

Press reports quoted students at a local high school as saying a car full of bearded men drove into the school's parking lot Saturday, dragging one of the victims from the bumper of their car. Students said the men fired weapons into the air and shouted that the Saudi boys should go to Iraq to help fight American soldiers. Saudi Crown Prince Abdullah said Sunday the kingdom will eliminate terrorism no matter how long it takes. He said Saudi Arabia would strike "with an iron fist" anyone who undermines the security of the country.

On Thursday, the State Department singled out Saudi Arabia for its exceptional work against terrorist networks.

About 50 people were killed in the kingdom last year following suicide bombings in the capital Riyadh. Five people were killed and nearly 150 others wounded less than two weeks ago (April 21) in a car bombing in the Saudi capital.