Biden says at least 11 American citizens killed during Israel conflict

US President Joe Biden on Monday said at least 11 American citizens were killed during ongoing hostilities in Israel and the occupied Palestinian territories.

"Sadly, we now know that at least 11 American citizens were among those killed—many of whom made a second home in Israel," Biden said in a statement, calling it "heart wrenching".

"We also know that American citizens still remain unaccounted for, and we are working with Israeli officials to obtain more information as to their whereabouts," he said.

Biden also added that his administration is still working to confirm and believe that "it is likely that American citizens may be among those being held by Hamas".

"I have directed my team to work with their Israeli counterparts on every aspect of the hostage crisis, including sharing intelligence and deploying experts from across the United States government to consult with and advise Israeli counterparts on hostage recovery efforts," Biden said.

"The United States and the State of Israel are inseparable partners, and I affirmed to Prime Minister Netanyahu again when we spoke yesterday that the United States will continue to make sure Israel has what it needs to defend itself and its people," he added.

Hamas launched Operation Al-Aqsa Flood against Israel early Saturday, firing a barrage of rockets and infiltrating Israel by land, air and sea. It said the surprise attack was in response to the storming of Al-Aqsa Mosque in occupied East Jerusalem and increased settler violence against Palestinians.

In retaliation, the Israeli military launched Operation Swords of Iron against Hamas in the Gaza Strip, killing at least 687 Palestinians and wounding at least 2,900 others.

At least 900 Israelis have been killed and over 2,600 others wounded in the fighting, according to local media.