Over 1,000 people in Lebanon have been killed in the last two weeks.
Israel's Lebanon operation continues as leaders consider their response to Iran's long-range attack on Tuesday, in which hundreds of missiles were fired into the country, according to Danny Danon, Israel's ambassador to the United Nations.
Iran said the unprecedented attack was retaliation for a wave of assassinations carried out by Israel over the last several weeks targeting Hezbollah, including leader Hassan Nasrallah.
Most of the missiles were intercepted, but "several hits were identified, and the damage is being assessed," an Israeli security official said.
Tune in to ABC News Live at 4 p.m. and 8:30 p.m. on Monday, Oct. 7, for "Oct 7th: Race to Survive" -- special coverage of the anniversary of the conflict. Veteran correspondent Matt Gutman highlights voices of Israelis and Palestinians impacted by the war and the ongoing humanitarian crisis in Gaza.
Israeli Prime Minister Benjamin Netanyahu said Iran's attack "failed" while vowing to respond.
"Iran made a big mistake tonight -- and it will pay for it," he said in a statement. "The regime in Iran does not understand our determination to defend ourselves and our determination to retaliate against our enemies."
"We will stand by the rule we established: Whoever attacks us -- we will attack him," he added.
In his first on-camera remarks since Iran's missile attack, President Joe Biden reiterated the United States' full support of Israel.
"Make no mistake, the United States is fully, fully, fully supportive of Israel," he said.
He said that at his direction, the U.S. military "actively supported the defense of Israel" and while they are still assessing the impact, the attack "appears to have been defeated and ineffective."
Biden said there was "intensive planning" between the U.S. and Israel to "anticipate and defend against the brazen attack we expected."
Asked how he would like Israel to respond, Biden said it was an "active discussion."
"We're gonna get all the data straight," he said. "We’ve been in constant contact with the Israeli government and our counterparts, and that remains to be seen."
-ABC News' Cheyenne Haslett
Talks between the United States and Israel on what a response to Iran's attack should look like are "already underway," State Department spokesperson Matthew Miller told reporters Tuesday.
Those conversations were happening across the State Department, the White House and the Pentagon, he said.
Miller declined to say whether Israel had presented possible targets to the U.S. or if Iran's nuclear facilities might be a legitimate target.
"This is not to say that I'm ruling anything out and that I'm ruling anything in,” he said.
On whether Iran's attack on Israel was over, Miller repeated the U.S. assessment that the current wave has ended, but that he could not definitively say whether there would be additional waves.
"Certainly, it would be incredibly reckless and would continue to be escalatory for Iran to launch further attacks on Israel and we’ll be monitoring in the hours ahead," he said.
-ABC News' Shannon K. Kingston and Emily Chang
Iranian President Masoud Pezeshkian said in a post on X that the attack on Israel was "based on legitimate rights and with the aim of peace and security for Iran and the region."
Pezeshkian also addressed Israeli Prime Minister Benjamin Netanyahu directly in his post: "Let Netanyahu know that Iran is not belligerent, but it stands firmly against any threat."
"This is only a tiny part of our power. Do not step into a conflict with Iran," Pezeshkian added.
-ABC News' Somayeh Malekian
