More than 2,800 people have died across both sides of the conflict in Gaza, according to The Associated Press.
U.S. Secretary of State Antony Blinken reported that the number of Americans killed in Israel is now at least 25.
"Tragically, the number of innocent lives claimed by Hamas' heinous attacks continues to rise. Among those, we now know that at least 25 American citizens were killed," Blinken said in Tel Aviv.
Blinken arrived in Israel Thursday morning amid the ongoing war with Hamas.
Blinken said shortly before heading to Israel that he will be working closely with the government of Israel to secure the release of those who have been apprehended by Hamas.
“We have a number of Americans who remain unaccounted; we are working very closely with the government of Israel to determine their whereabouts and, if they have been taken hostage by Hamas, to work to secure their release,” Blinken said.
The comments come as airstrikes intensify. On Thursday, Israeli warplanes struck a densely populated refugee camp in Gaza City, reducing whole buildings to rubble.
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The U.S. State Department says it will help arrange flights for U.S. citizens who want to leave Israel starting on Friday.
On Wednesday the State Department escalated its travel advisory to "reconsider travel" to Israel and the West Bank, due to the risks from terrorism and civil unrest. The U.S. already advised no travel to Gaza, due to the same threats.
The carrier strike group headed by the USS Gerald R. Ford has arrived in the Mediterranean, according to a U.S. official who spoke to The Associated Press.
The Pentagon said the flotilla would support sea and air operations, possibly including intelligence gathering and strikes against targets.
Another carrier strike group from Norfolk, Virginia, is set to depart for the region on Friday.
White House National Security spokesman John Kirby said on Thursday there is no plan for U.S. troops to deploy to Israel.
“There is no intention, no plan, and frankly, no desire by the Israelis,” Kirby said.
The United Nations humanitarian office says more people are fleeing the violence in Gaza, and warned that conditions are worsening by the hour for more than 200,000 people now sheltering in schools.
The morgue at Gaza's largest hospital ran out of room on Thursday, where medics say they've run out of places to put bodies recovered from demolished buildings.
The World Health Organization warned hospitals in Gaza are now running critically short of supplies, power and other resources.
"Without the immediate entry of humanitarian aid into Gaza — especially health services, medical supplies, food, clean water, fuel, and non-food items — humanitarian and health partners will be unable to respond to urgent needs of people who desperately need it. Each lost hour puts more lives at risk," the WHO said Thursday.
