The White House says Americans in Israel who want to leave but have been unable to find or cannot afford commercial flights will be evacuated on government chartered planes beginning Friday.

A spokesman for the National Security Council, John Kirby, told reporters in Washington that as many as four flights a day will be leaving Tel Aviv’s Ben Gurion national airport.

Mr. Kirby said the number of Americans confirmed killed in Saturday’s massacre by Hamas terrorists has risen to 27 and 14 are unaccounted for. A “handful” of those are believed to be held hostage in Gaza, he said. As of midday Thursday, according to Israeli authorities, more than 1,300 Israelis have been killed and another 3,000 wounded. Hamas is said to be holding 97 people hostage in Gaza.

“We continue to monitor the situation closely and evaluate the demand from U.S. citizens for assistance in departing Israel on a real-time basis but expect these initial travel options to facilitate the safe departure of thousands of U.S. citizens per week,” a U.S. Department of State spokesman said. “The overall security situation, availability and reliability of commercial transportation, and U.S. citizen demand will all influence the duration of this departure assistance.”

According to American government estimates, there are between 160,000 and 170,000 Americans in Israel at the moment, whether as visiting tourists or in some other capacity. Some 500 to 600 Americans are reportedly in Gaza and unable to leave because border exits have been sealed by Israeli and Egyptian authorities.

Mr. Kirby said Wednesday that America is in active discussions with Egypt to establish a safe corridor out of Gaza and allow those who want to leave to enter Egypt. According to the Times of Israel, Egyptian officials have so far rebuffed those efforts. In a visit to Israel Thursday, Secretary Blinken said the administration would continue its efforts.

There are still some commercial carriers flying in and out of Tel Aviv, and several ground routes to neighboring countries are open. One-way tickets on one of those airlines, Etihad, are listed at upward of $1,000 each. The White House said such options might not be feasible for all Americans wanting to leave the country, however.

Israel’s national carrier, El Al, announced Thursday that it would, for the first time in four decades, begin operating its planes on Saturdays, the Jewish sabbath, in order to bring reservists home from abroad. The airline said it received special dispensation from rabbis who said that preservation of life overrode other religious laws.