(NewsNation) — The number of Americans who have died in the Israel-Hamas war is now at 22, the State Department said Wednesday, an increase from the 14 reported on Tuesday.

President Joe Biden this week confirmed that U.S. citizens are among the estimated 150 hostages captured by Hamas after the Palestinian militant group’s attack on Israel by land, air and sea Saturday. Israel declared war after the attacks.

There are currently 17 U.S. citizens unaccounted for, National Security Council spokesperson John Kirby said at a White House press briefing Wednesday.

White House national security adviser Jake Sullivan said the United States does not know the exact number of Americans taken hostage at this time, though.

At least 2,200 people on both sides have been killed so far, the Associated Press is reporting — and the fighting is only expected to escalate. 

“Our hearts may be broken but our resolve is clear,” Biden said Tuesday, adding: “Let there be no doubt. The United States has Israel’s back. We’ll make sure the Jewish and democratic state of Israel can defend itself today, tomorrow as we always have.”

On Wednesday, he reiterated these sentiments, telling reporters “There’s no justification for terrorism.”

Hamas responded to Biden’s remarks with a statement saying it is fighting against an occupation and defending Palestinians’ right to self-determination.

A defense official confirmed to NewsNation the United States already had special operations personnel in Israel who are routinely stationed at the embassy.

U.S. Central Command and intelligence infrastructure in the region are helping Israel with planning and logistics for hostage rescues, the source also said.

However, Kirby and the Pentagon reiterated to NewsNation’s Kellie Meyer there are no plans for American boots on the ground.

Aiming to prevent a broader regional conflict, the nation’s newest and most advanced aircraft carrier, the U.S.S. Gerald R. Ford, arrived in the eastern Mediterranean Tuesday to deter more of Israel’s enemies from attacking.

A second aircraft carrier, the U.S.S Eisenhower, is set to leave Norfolk, Virginia in the coming days on route to the Mediterranean as part of its standard deployment schedule.

Both Biden and Vice President Kamala Harris spoke with Israeli Prime Minister Benjamin Netanyahu via phone on Wednesday.

Secretary of State Antony Blinken, meanwhile, is expected to leave for Israel on Wednesday and arrive Thursday. Blinken wrote on X, the social media site formerly known as Twitter, that once there, he will discuss with Israeli officials ways the U.S. can continue to support them.

The Associated Press contributed to this report.