“We extend our deepest condolences to the victims and to the families of all those affected, and wish those injured a speedy recovery.”

Though the NSC spokesperson did not say how many Americans were dead, Sen. majority leader Chuck Schumer, D-N.Y., said in a late Sunday statement issued following a State Department briefing on the fighting that they are so far aware of four Americans killed.

“But, sadly, we know the toll will rise,” he said.

More than 1,110 people — 413 Palestinians and some 700 Israelis — have been killed since Hamas launched a surprise multi-prong attack on Israel on Saturday, prompting Israeli Prime Minister Benjamin Netanyahu to launch retaliatory strikes and declare war against the militant and political group that overseas the Palestinian enclave of Gaza, which borders the Mediterranean Sea to the west and Israel to the north and east.

The confirmation comes hours after U.S. Secretary Antony Blinken announced on the Sunday news program circuit that they had received reports that Americans were among the dead and that others had also been taken hostage by Hamas, which is considered a terrorist organization by Israel, the United States and other Western allies.

Israeli Ambassador to the United States Michael Herzog told CBS News’ Face The Nation that dozens of people had been kidnapped by Hamas, and he understands Americans to be among them.

To reporters in New York City on Sunday, an irate Gilad Erdan, the permanent representative of Israel to the United Nations, described how some of the hostages were dragged from their homes and taken into Gaza.

“Mothers and their babies as well as babies separated from their mothers were brutally taken hostage,” he said.

“These are war crimes. Blatant, documented war crimes.”