Several U.S. nationals have been killed since Hamas' surprise attack on Israel on Saturday, a spokesperson for the U.S. National Security Council said Sunday, adding that U.S. officials continue to monitor the situation closely and remain in touch with their Israeli counterparts.
Earlier in the day, U.S. President Joe Biden held a phone conversation with Israeli Prime Minister Benjamin Netanyahu and said that "additional assistance for the Israeli Defense Forces is now on its way to Israel with more to follow over the coming days," the White House said in a statement.
(With input from Reuters)