The United States has issued a global alert warning its citizens abroad following an Iranian attack in Jordan that killed two servicemen and injured four others.

The U.S. Department of State issued the “worldwide caution” on Saturday, warning Americans in the diaspora, especially those in the Middle East.

“Worldwide Caution: Due to heightened tensions in the Middle East, the security environment remains complex with the potential for unforeseen escalation,” the security alert read.

It added, “We remind Americans in the region of the continued need for caution and encourage them to monitor the news for breaking developments.

“The Department of State advises Americans worldwide, and especially in the Middle East, to exercise increased caution. Americans abroad should follow the guidance in security alerts issued by the nearest U.S. embassy or consulate.”

According to the U.S. DoS, flight cancellations and periodic airspace closures may cause travel disruptions, adding that U.S. diplomatic facilities, including those outside the Middle East, have been targeted.

“Groups supportive of Iran may target other U.S. interests overseas or locations associated with the United States and/or Americans throughout the world,” it added.

Two United States service members were killed in Jordan as U.S. Central Command (CENTCOM) and allied forces intercepted Iranian ballistic missiles and drones during an attack.