The State Department is urging travelers to remain vigilant worldwide due to the escalating conflict in the Middle East.

In the wake of U.S. and Israeli bombing of nuclear sites in Iran, the alert warned of the potential for demonstrations and violence around the world.

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“The conflict between Israel and Iran has resulted in disruptions to travel and periodic closure of airspace across the Middle East,” the alert noted. “The Department of State advises U.S. citizens worldwide to exercise increased caution.”

Advisories for travel to Israel and Iran

Israel and Iran are under a Level 4: Do Not Travel advisory due to ongoing conflict. And while travel to Iran has been extremely limited for some time, more than 900,000 U.S. citizens go to Israel each year, according to the department.

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U.S. citizens in Israel or the West Bank are advised to “take the first available option,” in leaving the country, even if the destination wouldn’t be their first choice.

Ben Gurion Airport, the country’s busiest, remains closed and there are no regularly scheduled commercial flights or charter flights operating there.

The State Department is currently assisting with departure flights for U.S. citizens wanting to leave Israel. There are also land crossing available to Jordan and to Egypt, the department said.

Iranian airspace remains closed. U.S. citizens wishing to leave Iran are used to go by land to Azerbaijan, Armenia, or Turkey. Those who cannot leave are urged to shelter in place.