After an emergency government meeting on Sunday, Lebanon’s caretaker Economy Minister Amin Salam said officials were “feeling a bit more optimistic” about a de-escalation between Israel and Hezbollah.

“We feel more reassured since both sides confirmed that the expected operations ended,” he said, referring to Sunday morning's heavy exchange of hostilities between Israel and Hezbollah.

Waking at dawn on Sunday to explosions and sirens, Abigail Levy checked the news and quickly understood there had been "an escalation" of hostilities between Israel and Hezbollah.

Hezbollah chief Sayyed Hassan Nasrallah on Sunday announced that Hezbollah’s attack on Israel on Sunday morning had targeted an intelligence base just outside Tel Aviv and an air defense base in the heart of Israel.

“We targeted the Glilot military intelligence base near Tel Aviv, around 110 kilometers from Lebanon's border,” said Nasrallah in a speech dedicated to explaining Hezbollah’s response to the killing of its top military chief Fouad Shukur, who was assassinated in an airstrike on Beirut’s southern suburbs around a month ago.

Israeli Prime Minister Benjamin Netanyahu warned that Sunday's strikes in Lebanon were "not the final word" in Israel's military campaign against Hezbollah.

Israel has told foreign parties that it moved to thwart a major Hezbollah attack on Sunday morning and that it does not intend to “turn that into a broad war,” the Israel Hayom newspaper said.

Beirut airport was functioning Sunday but many passengers were stuck as flights were cancelled or delayed, an AFP correspondent said, after Israel and Hezbollah announced broad strikes in an escalation of cross-border hostilities.

"We came at 4:30 am for our flight at 8:00 am but they told us it was cancelled," said Elham Shukair, a passenger headed to the United States via Jordan.

Palestinian Islamist movement Hamas on Sunday hailed strikes by Lebanon's Hezbollah against Israel, calling it a "strong and focused response".

"We emphasize that this strong and focused response, which struck deep inside the Zionist entity, is a slap in the face" for the Israeli government, Hamas said in a statement after Hezbollah said it launched a large-scale operation using rockets and drones.

On the deserted border between Lebanon and Israel, Spanish U.N. peacekeepers have for more than 10 months effectively been caught in a war zone.

Several Blue Helmets have been wounded in the crossfire between Israel and Lebanon's Hezbollah, which has also left dozens of Lebanese civilians dead in fallout from the Israeli war on Gaza.

The United States said its commitment to Israel's defense was ironclad and that it was "postured" to support its ally after the Israeli military said Sunday it had launched strikes in Lebanon to prevent a major attack by Hezbollah.

U.S. Defense Secretary Lloyd Austin had spoken with Israeli counterpart Yoav Gallant about Israel's defense against attacks by the Iran-backed Lebanese militant group, Pentagon spokesman Major General Pat Ryder said.

Hezbollah, which has exchanged fire with Israeli forces since October, last went to war with Israel in 2006 and has since expanded its domestic and regional influence, politically and militarily.

Financed and armed by Iran, Hezbollah is the most prominent actor in the so-called axis of resistance -- regional pro-Tehran armed groups opposed to Israel that also include Palestinian militants Hamas, Iraqi movements and Yemen's Houthi rebels.