Family members of employees at US embassies in the United Arab Emirates, Jordan, Qatar and Bahrain have also been ordered to return to the US, according to an AFP source.
At 9:30 p.m. on Wednesday, Saudi Arabia's Energy Ministry said two people were killed and two others injured when air defenses shot down a drone at an oil facility near the border with the United Arab Emirates. It is unclear who was behind the attack.
The attack and the information about the embassy staff come at a time when the Gulf state is under heavy attack from the Iran-backed Houthi movement in Yemen.