Flames and thick smoke rose from an Aramco facility south of Riyadh on Saturday after Yemen's Houthi rebels claimed they targeted the site with ballistic missiles and drones.
An AFP journalist and a Reuters witness at the scene reported seeing fire engines, ambulances, and police vehicles responding to the burning refinery.
The incident follows Houthi claims of 26 Saudi airstrikes on Sanaa and escalating hostilities targeting Saudi energy infrastructure.