US blames Iran for attack on two big Saudi oil sites
Yemen's Houthi rebels launched drone attacks on the world's largest oil processing facility in Saudi Arabia and a major oil field Saturday (local time), sparking huge fires at a vulnerable chokepoint for global energy supplies.
According to multiple news reports that cited unidentified sources, the drone attacks affected up to half of the supplies from the world's largest exporter of oil, though the output should be restored within days.
It remained unclear if anyone was injured at the Abqaiq oil processing facility and the Khurais oil field.
The attack by the Iranian-backed Houthis in the war against a Saudi-led coalition comes after weeks of similar drone assaults on the kingdom's oil infrastructure, but none of the earlier strikes appeared to have caused the same amount of damage.
The attack likely will heighten tensions further across the Persian Gulf amid an escalating crisis between the US and Iran over its unraveling nuclear deal with world powers.
US Secretary of State Mike Pompeo contested claims the Houthis were directly involved.
"There is no evidence the attacks came from Yemen," he said, calling it an "unprecedented attack on the world's energy supply".
How the attack unfolded
First word of the assault came in online videos of giant fires at the Abqaiq facility, some 330 kilometres northeast of the Saudi capital, Riyadh.
Machine-gun fire could be heard in several clips alongside the day's first Muslim call to prayers, suggesting security forces tried to bring down the drones just before dawn.
In daylight, Saudi state television aired a segment with its local correspondent near a police checkpoint, a thick plume of smoke visible behind him. Smoke from the fires could be seen by satellites.
The fires began after the sites were "targeted by drones", the Interior Ministry said in a statement carried by the state-run Saudi Press Agency. It said an investigation was underway.
Saudi Aramco, the state-owned oil giant, did not respond to questions from The Associated Press.
In a short address aired by the Houthi's Al-Masirah satellite news channel, military spokesman Yahia Sarie said the rebels launched 10 drones after receiving "intelligence" support from those inside the kingdom.
He warned that attacks by the rebels would only get worse if the war continues.
"The only option for the Saudi government is to stop attacking us," Mr Sarie said.
Why the rebels attacked
The rebels hold Yemen's capital, Sanaa, and other territory in the Arab world's poorest country. Since 2015, a Saudi-led coalition has fought to reinstate the internationally recognised Yemeni government.
President Donald Trump called Saudi Arabia's Crown Prince Mohammed bin Salman in the wake of the drone strikes and expressed the United States' readiness to cooperate with the kingdom in supporting its security and stability, according to a news release from the Saudi Embassy in Washington.
Mr Trump said recent attacks against Saudi state-run oil facilities have had a negative impact on the US and global economies.
The crown prince assured Mr Trump that Saudi Arabia is "willing and able to confront and deal with this terrorist aggression", according to the release.
The US Embassy in Riyadh said it was unaware of any injuries to Americans. Saudi Aramco employs a number of US citizens, some of whom live in guarded compounds near the site.
"These attacks against critical infrastructure endanger civilians, are unacceptable, and sooner or later will result in innocent lives being lost," US Ambassador John Abizaid, a former Army general, said.
What impact will the attack have on oil production?
Saudi Aramco describes its Abqaiq oil processing facility in Buqyaq as "the largest crude oil stabilisation plant in the world".
The facility processes sour crude oil into sweet crude, then transports it onto transshipment points on the Persian Gulf and the Red Sea or to refineries for local production.
Estimates suggest it can process up to seven million barrels of crude oil a day. By comparison, Saudi Arabia produced 9.65 million barrels of crude oil a day in July.
The plant has been targeted in the past by militants. Al-Qaida-claimed suicide bombers tried but failed to attack the oil complex in February 2006.
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