Secretary of State Antony Blinken stressed that the U.S. is exploring all options in getting the American citizens who were taken by Hamas forces back safely during an interview Thursday with "World News Tonight" anchor David Muir.

He would not say if those plans included using U.S. Special Forces.

"I'm not going to get into the specifics of what we're looking at considering, unfortunately, [that] we have a lot of experience with this over the years," Blinken told Muir. "President Biden has always been determined in these situations to explore every possible option. That's what we’re doing."

Blinken added that the U.S. is working with other countries "who may have leverage with Hamas to use that leverage in favor of getting the hostages home."

-ABC News' Ivan Pereira

In an interview Thursday with "World News Tonight" anchor David Muir, Secretary of State Antony Blinken expressed his disgust and anger with Hamas after he saw the gruesome details from last weekend's attack.

During a meeting with Israeli Prime Minister Benjamin Netanyahu earlier in Israel, Blinken said he was shown images and videos of the victims who were killed and wounded during last weekend's attack.

Blinken said that the images, many of which were not seen before, were "genuinely overwhelming."

"A young infant riddled with bullets, a family hugging each other, in a death embrace, having been burned to death, beheaded soldiers," Blinken said, describing what he saw. "It almost defies human comprehension precisely because it's not human."

-ABC News' Ivan Pereira

New York City Mayor Eric Adams said there are "no credible or specific threats" against the city ahead of Friday, when Hamas is calling on their supporters to hold worldwide "Day of Rage" protests that could turn violent.

"We are deeply disturbed by the message of hate. It is not acceptable," Adams said during a briefing.

The mayor said he has directed the NYPD to surge additional resources to schools and houses of worship "to ensure that they are safe." Police are also stepping up patrols in certain neighborhoods, he said.

New York Gov. Kathy Hochul also said at the briefing there is no intelligence "showing any active threats" in the state but "we will continue to exercise elevated vigilance."

She said state police have been "fully activated" and the National Guard has been directed to patrol key transportation hubs.

"There's no reason to feel afraid," Hochul said.

In an interview with ABC News Live, Michael Oren, the former Israeli ambassador to the U.S., warned that we are just at the "beginning of this war."

Oren said the possibility of another front is "almost certain now," saying he thinks Hezbollah will join the conflict. He also warned that this war will differ from past ones in the region like the Six Day War and Yom Kippur War because this will be fought in locations that are densely populated with civilians.

"This war, by very marked contrast, is fought in the Israeli heartland," Oren said. "It is the vast majority of our casualties are civilians. We're fighting against an enemy that wants to destroy us at any cost and will do so in the most brutal manner and massacre our civilians."

Oren said the support from the U.S. has been crucial during a time of great "agony."

"To have the leaders of the most powerful country in the world, to come out in support of us in that way, so categorically, so unequivocally condemning terror was very moving for all of us, a great source of relief," Oren said.

The families of 155 Israeli soldiers have received death notices so far, the Israel Defense Forces said.