An oil field and a crucial oil-processing site in Saudi Arabia were targeted by drones in an attack early on September 14, the kingdom's Interior Ministry said.
The attack on the oil-processing facility in Buqyaq, crucial to global energy supplies, sparked a large blaze.
Saudi Aramco, the state-owned oil giant, did not immediately respond to questions from the AP news agency.
Saudi Aramco describes its Abqaiq oil-processing facility in Buqyaq as 'the largest crude oil stabilization plant in the world.'
No one immediately claimed responsibility for the attack in Buqyaq and the Khurais oil field, although Yemen's Huthi rebels have in the past launched drone strikes inside Saudi Arabia.
A Saudi-led coalition has been battling the Iran-backed Huthi rebels since March 2015.
It was unclear if there had been injuries in the attacks and there was no information on the scale of the damage caused.
Online videos apparently shot in Buqyaq included the sound of gunfire in the background.
Smoke rose over the skyline and glowing flames could be seen a distance away at the Abqaiq facility.
Based on reporting by AP, Reuters, and AFP
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