Washington: Eleven US citizens have died in the conflict in Israel, President Joe Biden said Monday, and an unknown number remain missing.

“As we continue to account for the horrors of the appalling terrorist assault against Israel this weekend and the hundreds of innocent civilians who were murdered, we are seeing the immense scale and reach of this tragedy,” Biden said in a statement. “Sadly, we now know that at least 11 American citizens were among those killed—many of whom made a second home in Israel.”

It is “likely,” Biden said, that American citizens may be among those being held hostage by Hamas, and his administration is working with Israeli officials on “every aspect of the hostage crisis.” There are also American citizens whose whereabouts remain unaccounted for, according to the president.

“This is not some distant tragedy. The ties between Israel and the United States run deep,” he said. “It is personal for so many American families who are feeling the pain of this attack as well as the scars inflicted through millennia of antisemitism and persecution of Jewish people.”