Suspected Islamist militants shot dead at least four Westerners, two Saudi guards and an Egyptian boy and seized hostages in triple attacks Saturday targeting oil facilities in eastern Saudi Arabia, residents and diplomatic sources said.
The assault, the latest in a wave of terror to hit Saudi Arabia over the past year, was claimed by the Al-Qaeda network of Saudi-born Osama bin Laden, although the authenticity of the claim could not be independently confirmed.
Men, women and children were taken hostage at The Oasis housing compound in the oil city of Al-Khobar, on the Gulf coast one diplomat said.
Security forces exchanged fire with the gunmen who were holed up in the compound with their hostages, the diplomat added.
Five Lebanese among the group were later freed, Lebanon's ambassador in Riyadh, Ahmad al-Mashat, said.
A week after a German was gunned down in the capital Riyadh, at least four Westerners died under a hail of bullets in the Al-Arrakah area of Al-Khobar, five kilometres (three miles) from the Oasis, residents said.
A Western diplomatic source said the dead included one Briton, but both US and British diplomats said they could not immediately confirm reports that an American and a Briton were among the fatalities.
Four suspected Islamist radicals also attacked an adjacent building of the Arab Petroleum Investment Corp. (Apicorp) during the morning, killing two guards, said a senior official with the Saudi-based company, an arm of the Organization of Arab Petroleum Exporting Countries.
"At least four terrorists attacked the company building this morning and clashed with security guards," the official said, asking not to be named. An Egyptian boy caught in the crossfire also died, he said.
An Egyptian diplomatic source named the 10-year-old as Rami Samir al-Ghunaimi.
The official would not comment on reports from residents that at least four Westerners had been killed and many wounded at the neighbouring compound in an area popular with foreign oil workers.
Police guards fired back at the attackers, local people said.
Before the hostage taking at The Oasis, a nearby "Petroleum Centre" where oil firms, including Anglo-Dutch giant Shell, have offices, also came under attack, the official said.
He added that he thought that the same gunmen were involved in all the attacks.
The 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. We will give details later, naming the heroes of our blessed squad," it said.
The statement suggested that the assault against the facilities "affiliated to the US occupation company Halliburton" was ongoing, and said the attackers were "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, Iraq and everywhere," it said.
Al-Qaeda and affiliates have often claimed responsibility in similar statements for the past year's campaign of terror in he kingdom which have 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 which 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, which was in fact 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 come down to 18 since it was released amid a relentless 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, saying the kingdom's oil fields and facilities were well-protected.
"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.