Riyadh (AsiaNews) – Saudi officials are hailing as a great success their rescue mission to free foreign workers held hostage by Islamic militants in the oil city of Khobar. An estimated 50 hostages were rescued from the building by the helicopter-borne troops who ended 25 hours of violence that left 22 people dead during the attack and  while being held captive.

One militant was captured, but three others escaped despite the massive presence of security forces.

The dead comprised eight Indians, three Filipinos, three Saudis, two Sri Lankans, an American, a Briton, an Italian, a Swede, a South African and an Egyptian. Nine of the hostages - seven Asians, the Swede and the Italian - had their throats slit during the night

An internet statement signed by the "al-Qaeda network in the Arabian Peninsula" said  it carried out the hostage-taking because it vowed to rid the peninsula of "infidels". Saudi-born bin Laden has vowed to undermine the kingdom for its close ties to Washington.

The attack started on Saturday, when gunmen in their late teens and early 20s opened fire on three compounds in Khobar. Several people were killed. Then  the attackers stormed the Petroleum Centre headquarters about 3km away, where at least four people were killed. The Petroleum Centre is the seat of many oil companies such as the Dutch- Shell, the French Total; the Russian Lukoil; the Chinese Sinopec. Among the victims on the road there was also an Egyptian boy, who was found in a school bus.  Finally  the terrorists moved to the Saad Centre, a residential building in the luxurious Oasis compound, where they took an estimated 50 hostages and raise barricades.

According to many witnesses the gunmen had barged into homes looking for foreigners and non-Muslims.

"The terrorists' goal is to disrupt the Saudi economy and destabilise our country. But they will not succeed," Prince Bandar said.

 Khobar, 400km (250 miles) north-east of Riyadh, is one of the centres of the Saudi oil industry, in which foreigners play a key role.

In early May, five foreigners were killed in an attack on a petrochemical site in the city of Yanbu.  A string of suicide bombings in Riyadh last year killed about 50 people.