At least nine Americans have been killed and others are still missing after Hamas’ surprise weekend attack on Israel, the State Department said Monday — as a team of US veterans are prepping to fly out to help rescue trapped citizens.

“At this time, we can confirm the deaths of nine US citizens,” State Department spokesperson Matthew Miller said in a statement — raising the earlier death toll from four.

“We can confirm that there are unaccounted-for US citizens, and we are working with our Israeli partners to determine their whereabouts.”

It wasn’t immediately clear how many Americans were still missing, though a US official said Sunday the number was fluid and had ranged from between six to 12.

It is not known yet whether the missing were among those who were taken hostage, were killed or are still in hiding.

The State Department is in touch with families “and providing all appropriate consular assistance,” Miller said.

The Americans killed in the conflict have yet to be identified by officials in the US.

The unprecedented attack by Hamas on Saturday has left more than 1,000 dead on both sides.

Fighters from Islamist group killed 700 Israelis, left roughly 2,000 injured and abducted dozens more as they attacked Israeli towns on Saturday — the deadliest onslaught the nation has seen in more than 50 years.

At least 260 people were killed in a massacre at the Tribe of Nova music festival in Israel after heavily armed Palestinian terrorists paraglided across the Gaza Strip border.

Israel responded to the sneak attack by pounding Gaza, killing hundreds of Palestinians.

The US Embassy in Jerusalem had put out an order for Americans to “shelter in place” during Saturday’s assault, with the office updating its contingency plans “for any potential evacuation by land or air.”

Meanwhile, the non-profit Project DYNAMO said its US veterans are shipping out to Israel in a desperate attempt to free trapped Americans after previously helping in Afghanistan.

Bryan Stern, CEO and founder of the group, said his team has already received hundreds of requests from Americans, their families and other allies who need assistance under the organization’s Operation: PROMISED LAND as Hamas continues to kidnap individuals.

“Probably the actual number is five, six, seven, or eight [times] that that need help,” he told WUSF.

The group — comprising a team of special operations and intelligence community veterans, as well as civilian volunteers — has already mobilized assets in the region and initiated emergency launch preparations of its American Operations team for potential evacuation and hostage rescue operations.

Stern, himself, is also heading to Israel to lead the operations.

“We are aggressively monitoring this grave situation, collecting intelligence and receiving requests for assistance,” he said in a statement. “We are likely forward deploying an American operations team very shortly to supplement our assets already operating on the ground.”

In the wake of the bloodshed, Defense Secretary Lloyd Austin said Sunday he had ordered the Ford carrier strike group to sail to the Eastern Mediterranean to be ready to assist Israel.

The USS Gerald R. Ford, the Navy’s newest and most advanced aircraft carrier, and its approximately 5,000 sailors and deck of warplanes will be accompanied by cruisers and destroyers in a show of force.

“The U.S. maintains ready forces globally to further reinforce this deterrence posture if required,” Austin said.

In addition, the Biden administration “will be rapidly providing the Israel Defense Forces with additional equipment and resources, including munitions. The first security assistance will begin moving today and arriving in the coming days,” Austin said.

With Post wires