AL-KHOBAR, Saudi Arabia (AFP) - Suspected Islamist militants killed at least 11 people, including an American and an Egyptian boy, and then holed up with hostages in a series of spectacular attacks on oil facilities in Saudi Arabia.
The Al-Qaeda network of Saudi-born Osama bin Laden has purportedly claimed the asault in Al-Khobar, the latest in a wave of terror to hit the kingdom over the past year, but authenticity of the claim could not be independently verified.
There was no official confirmation of the death toll compiled from residents, diplomats and an oil company executive.
Saudi security forces had besieged the assailants, who were barricaded in a six-storey building with an undetermined number of hostages as evening began after a day of carnage.
Three Western nationals escaped from The Oasis residential compound where the hostage drama was unfolding and said they had seen the body of a woman drenched in blood.
The US embassy in Riyadh said one American was among the dead.
Western diplomatic sources said a Briton was also slain, but British diplomats had yet to confirm it.
An official at the Arab Petroleum Investment Corp. (Apicorp), one of the targeted facilities, said two Saudi guards were killed, in addition to two Asian nationals -- a Pakistani and a Filipino.
An Egyptian boy caught in the crossfire also died. An Egyptian diplomatic source named the 10-year-old as Rami Samir al-Ghunaimi.
Witnesses said four Saudi security men were also killed in a shootout with the gunmen Saturday morning at The Oasis compound.
A statement from the interior ministry said only that "a number of citizens and (foreign) residents were killed or wounded" after four gunmen "shot indiscriminately at the premises of a company and a residential compound in Al-Khobar" at 7:30 am (0430 GMT).
The gunmen "then entered a residential compound, where they were besieged by security forces in a building. They are being dealt with in accordance with the requirements of the situation," the statement said.
A Lebanese man reported to have been taken hostage said he and his family were locked in their home several hours after the attacks began.
"At 9:00 am (0600 GMT), a gunman knocked at the door of our villa, checked whether we were foreigners (Westerners), and ordered us to stay at home, saying he and his comrades were outside," Abdel Salam Hakawati told AFP by telephone.
Hakawati, his wife and son, in addition to two other Lebanese nationals, were earlier reported by diplomats to have been taken hostage and later released.
Four gunmen attacked an adjacent Apicorp building during the morning, killing two guards, a senior official with the Saudi-based company, an arm of the Organization of Arab Petroleum Exporting Countries, told AFP.
Before the hostage-taking, a nearby "Petroleum Centre" where oil firms have offices, also came under attack, the official said.
The purported Al-Qaeda claim of responsibility came in a statement received by e-mail.
"The heroic mujahedeen in the Jerusalem Squad were able, by the grace of God, to raid the locations of American companies ... specializing in oil and exploration activities and which are plundering the Muslims' resources, on Saturday morning," said the statement, signed by the "Al-Qaeda Organization in the Arabian Peninsula."
"They have so far managed to kill or wound a number of crusaders, God's enemies," it said.
The statement said the assault targeted the facilities "affiliated to the US occupation company Halliburton" and praised the attackers as "an honorable example of Muslim youth in the Arabian Peninsula."
There are many like them, "competing to meet martyrdom, eager to fight God's enemies -- the Jews, the crusaders and their stooges among the apostate rulers -- as their hearts grieve for what has befallen their Muslim brethren in Palestine, Afghanistan (news - web sites), Iraq (news - web sites) and everywhere," it said.
Al-Qaeda and affiliates have often claimed responsibility in similar statements for the past year's campaign of terror in the kingdom which has left some 65 people dead and hundreds injured.
A statement purported to be from the network's chief in Saudi Arabia, Abdul Aziz al-Muqrin, said an Al-Qaeda cell carried out a May 1 shooting rampage at a petrochemical plant in the industrial port of Yanbu that left six Westerners dead.
As in the aftermath of the Yanbu carnage, Saturday's bloodshed seemed likely to provoke a new surge in oil prices that had already closed higher Friday amid fears of unwelcome developments over the weekend.
It followed a statement purported to be from Muqrin and posted on an Islamist website Thursday which urged followers to wage an urban guerrilla war of assassinations, kidnappings and bombings.
The authenticity of the lengthy statement could not be independently confirmed and appeared to be several months old. It referred to a Saudi announcement "in recent days" of a list of 26 most-wanted terror suspects. That list was issued in December following a series of suicide bombings that targeted residential compounds in Riyadh in May and November 2003.
Muqrin tops the list of wanted suspects, which has dropped to 18 since it was released amid a massive crackdown by security forces on suspected Al-Qaeda sympathizers.
Germans were warned Sunday to take extra care after Hermann Dingel, a caterer with Saudi Arabian Airlines, was gunned down outside a bank in Riyadh's Al-Hamra district last Saturday evening.
Few extra details have emerged of the murder but the German embassy suspected a terror attack.
In mid-April, the United States ordered its non-essential diplomats in Saudi Arabia to leave and urged US citizens in the kingdom, who numbered about 30,000, to depart.
Saturday's carnage came after the chief executive of the Saudi state oil monopoly Aramco tried to ease Western fears over oil supplies.
"Our company has 5,000 security guards to protect oil facilities, in addition to the state security forces deployed around them," Abdullah Jumah said at the Royal Institute of International Affairs in London on Wednesday.
"Land, marine and border forces are involved in the security operation to prevent terrorists and saboteurs from reaching oil facilities on land and sea."
The head of Aramco, which employs some 54,000 people, including 2,300 US and Canadian citizens and about 1,100 Europeans, said Saudi Arabia would have no trouble producing 12 to 15 million barrels a day.