The statement from the Israeli prime minister's anti-terror office took the unusual step of calling on families of Israelis visiting the Sinai to establish contact with them.
Israel's anti-terror office has a standing travel advisory telling Israelis to stay out of the Sinai desert because of the threat of terror attacks. However, thousands of Israelis routinely ignore the warning and vacation in the desert and along its Red Sea coast.
Egyptian security officials said about 35,000 Israelis are in the Sinai now, and they expected thousands more to arrive later this month.
In the unusually strong statement, the Israeli anti-terror office called "on all Israelis residing in Sinai to leave immediately and return home. Families of Israelis residing in Sinai are asked to contact them and update them on the travel warning."
In 2004, suicide bombers attacked Egypt's Taba Hilton Hotel, just across the Israeli border, and several campsites where Israelis are known to vacation. Dozens of people were killed and hundreds wounded.
Israel controlled the Sinai from its capture in the 1967 war until returning it to Egypt in 1982 in the framework of a peace treaty between the two nations. (Source)