(NewsNation) — The U.S. State Department urged Americans not to go to Gaza and reconsider travel to Israel and the West Bank in advisories issued Wednesday.

“Terrorist groups, lone-actor terrorists and other violent extremists continue plotting possible attacks in Israel and the West Bank and Gaza,” the State Department said. “Terrorists and violent extremists may attack with little or no warning, targeting tourist locations, transportation hubs, markets/shopping malls and local government facilities.”

Israel declared war after militant group Hamas attacked Saturday. Since then, Israel has called up hundreds of thousands of reserve troops, and its Defense Forces are deploying more troops and artillery to the country’s border with Gaza.

At least 2,600 lives have been claimed on both sides in the war, the Associated Press reports, and fighting is expected to escalate.

The number of Americans killed was at 27 as of Wednesday afternoon, National Security Council spokesperson John Kirby said. There are 14 currently unaccounted for.

Americans still planning to travel to Israel, the West Bank and Gaza right now should maintain a “high degree of situational awareness” and “exercise caution at all times” and avoid demonstrations and crowds, the State Department said. People going to these areas can also register in the Smart Traveler Enrollment Program to make it easier for them to be located in an emergency.

The United Kingdom has similar advisories urging people against traveling to parts of Israel and the Occupied Palestinian Terrorities at this time.

The Associated Press contributed to this report.