Drone attacks have set alight two major oil facilities run by the state-owned company Aramco in Saudi Arabia, state media say.
Footage showed flames and huge palls of smoke over Abqaiq, which has the world’s largest oil processing plant.
A second drone attack also started fires in the Khurais oil field to the west. The fires are now under control at both facilities, state media said.
Iran-aligned Houthi fighters in Yemen have been blamed for previous attacks.
However, the Saudi media reports did not say who could be behind the latest attacks.
“At 04:00 (0100 GMT), the industrial security teams of Aramco started dealing with fires at two of its facilities in Abqaiq and Khurais as a result of… drones,” the official Saudi Press Agency reported.
“The two fires have been controlled.”
Abqaiq is about 60km (37 miles) south-west of Dhahran in Saudi Arabia’s Eastern Province, while Khurais, some 200km further south-west, has the country’s second largest oilfield.
Houthi fighters were blamed for drone attacks on the Shaybah natural gas liquefaction facility last month and on other oil facilities in May.
However, Saudi Arabia also blamed Iran for attacks in the Gulf on two oil tankers in June and July, allegations Tehran denied.