For an operation now dubbed "Swords of Iron," the Israel Defense Forces said Monday that it had struck 500 Hamas and Islamic Jihad targets in the Gaza Strip.

The attacks were carried out through the use of jets, helicopters and other aircraft, according to the IDF.

The IDF said seven of Hamas' command centers were struck in the mission.

-ABC News' Bruno Nota

An Iranian official at the UN denied that Iran had any involvement in Hamas' attack on Israel.

Israeli officials, including President Isaac Herzog, had claimed on Saturday that Iran helped coordinate the attacks on Israel.

On Sunday, however, Iran's Mission to the UN, denied the claims.

“We emphatically stand in unflinching support of Palestine; however, we are not involved in Palestine's response, as it is taken solely by Palestine itself.,” the Iranian Mission to the UN said in a statement late Sunday. “The resolute measures taken by Palestine constitute a wholly legitimate defense against seven decades of oppressive occupation and heinous crimes committed by the illegitimate Zionist regime.”

A U.S. official said Saturday it was "too early" to tell if Iran had involvement in the attacks.

"We are going to be looking at that very closely," a senior administration official said.

-ABC News' Kirit Radia

Israeli Defense Forces attacked the Gaza Strip early Monday morning local time, the IDF said in a series of posts on X, the platform formerly known as Twitter.

The IDF attacked a building where it said Hamas operatives were and several operational headquarters of the organization, the IDF said in the posts.

-ABC News’ Ellie Kaufman

An emergency meeting of the United Nations Security Council failed to condemn the Hamas attacks on Israel Sunday evening.

Deputy U.S. Ambassador the U.N. Robert Wood said the situation was "still fluid" and "very dangerous."

"What is important now is that the international community needs to show its solidarity with Israel. We have Israel's back fully as the United States, and the condemnation of Hamas needs to continue until they end this violent terrorist activity against the Israeli people," Wood said after the meeting.

-ABC News' Ellie Kaufman

National Security Council spokesperson John Kirby avoided saying if the U.S. believed Israel's calls for civilians in Gaza to evacuate in the next 24 hours was possible but acknowledge that it was a "tall order" given how densely populated the area is.

"Well, I think we're going to be careful not to get into armchair quarterbacking the tactics on the ground by the IDF. What I can tell you is we understand what they're trying to do. They're trying to move civilians out of harm's way and giving them fair warning. Now, it's a tall order. It's a million people, and it's a very urban, dense environment, already a combat zone. I don't think anybody's underestimating the challenge here of affecting that evacuation," Kirby said in an interview on CNN Friday morning.

"But it's pretty clear that what they're trying to do is to the maximum extent possible avoid civilian casualties and also separate Hamas from the human shields. I mean, Hamas actually gave a counterorder telling Palestinians in Gaza to stay at home. Why? Because having human shields, they think, protects them," Kirby continued.

Asked about their efforts to secure a safe passage for civilians out of Gaza, Kirby reiterated that the U.S. is talking to Israel and Egypt but would not comment further on progress.

On the Rafah crossing specifically, Kirby said "So far it's still closed. But that doesn't mean were not going to still try as hard as we can to talk to the Israelis and Egyptians about getting it open and having some sort of safe passage out. It's important that we also continue to work to make sure that humanitarian assistance can get in. The United States has no intention of stopping our efforts to continue to deliver humanitarian assistance, but there has to be a path in, there has to be a path out."

Kirby had no update on the Americans who are believed to be held hostage in Gaza and could not confirm reports that 13 hostages have been killed by Israeli airstrikes, as Hamas has claimed.

-ABC News' Molly Nagle