Yemen's Huthi rebels have claimed responsibility for two drone attacks on oil facilities operated by Saudi Aramco earlier on September 14.
Saudi Arabia's Interior Ministry said an oil field in Khurais Province and an oil-processing facility, the world's biggest, in Abqaiq Province, were targeted in the drone strikes.
The attacks sparked fires, which Saudi authorities later said were brought under control.
Several hours after the predawn attacks, Aramco has issued no statement and the authorities have not reported on casualties.
State television said exports were continuing.
Abqaiq is located 60 kilometers southwest of Aramco's Dhahran headquarters. It contains the world's largest oil-processing plant, handling crude from the giant Ghawar field and for export to terminals Ras Tanura -- the world's biggest offshore oil-loading facility -- and Juaymah. It also pumps westwards across the kingdom to Red Sea export terminals.
Khurais, 190 kilometers further southwest, contains the country's second-largest oil field.
Saudi Arabia has led a coalition of Sunni Muslim countries that intervened in Yemen in 2015 against the Shi'ite Huthis.
Riyadh has blamed regional rival Shi'ite Iran for previous attacks, which Tehran denies. Riyadh accuses Iran of arming the Huthis, a charge denied by the group and Tehran.
The war has become the world's worst humanitarian crisis. The violence has pushed Yemen to the brink of famine and killed more than 90,000 people since 2015, according to the U.S.-based Armed Conflict Location & Event Data Project, or ACLED, which tracks the conflict.
Since the start of the Saudi-led war, Huthi rebels have been using drones in combat.
The rebels have flown drones into radar range of Saudi Arabia's Patriot missile batteries, according to Conflict Armament Research, disabling them and allowing the Huthis to fire ballistic missiles into the kingdom unchallenged.
UN investigators said the Huthis' new UAV-X drone, found in recent months during the Saudi-led coalition's war in Yemen, likely has a range of up to 1,500 kilometers.
With reporting by Reuters, AP, and AFP
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