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.
The Israel Defense Forces' ground movement into Lebanon will be significant but not "major," a senior U.S. official told ABC News.
The operations will be limited to small unit commando teams, the official said, adding that the teams will have air power backup against Hezbollah fighters.
-ABC News' Martha Raddatz
The Israeli Defense Forces issued an "urgent warning" Monday to residents of the southern suburbs of Beirut.
In a post on X, the IDF urged people in three neighborhoods -- Lilac, Haret Hreik and Burj Al-Barajneh -- to evacuate.
“You are located near interests and facilities belonging to the terrorist Hezbollah, and therefore the IDF will act against them forcefully," the IDF wrote. "For your safety and the safety of your family, you must evacuate the buildings immediately, starting at a distance of no less than 500 meters."
On Monday, UNRWA chief Philippe Lazzarini denied having being aware that staffer Fateh Sherif Abu el-Amin had been the head of Hamas' Lebanon branch.
Abu el-Amin and his family were killed in an Israeli airstrike in southern Lebanon, a spokesperson for Hamas said Monday.
In his press briefing in Geneva on Monday, Lazzarini said Abu el-Amin had been suspended from his UNRWA position in March after allegations arose that he was involved in Hamas.
-ABC News' William Gretsky
Five people were killed and 57 were injured after Sunday's Israeli air strikes in Al-Hodeidah, Yemen, the Houthi spokesperson said in a statement Monday.
"This crime will be responded to with escalating military operations against the criminal enemy during the coming period," the Houthi spokesperson added in his statement.
-ABC News’ Ahmed Baider
