Israel launched deadly cross-border strikes Friday on Hezbollah targets in Syria and Lebanon, doubling down on Iran-backed foes and Hamas allies, and fuelling concerns the violence could spark a major regional conflagration.

The Israeli army said it killed the deputy head of Hezbollah's rocket unit, Ali Naim, in one of the attacks on southern Lebanon.

An Israeli strike killed the deputy head of Hezbollah's rocket unit in south Lebanon on Friday, the Israeli military said, the latest deadly cross-border violence since the Israel-Hamas war erupted.

Hezbollah, which has a powerful arsenal of rockets and missiles, has exchanged near-daily fire with the Israeli army since its ally, Palestinian militant group Hamas, carried out an unprecedented attack on southern Israel on October 7, triggering war in Gaza.

An Israeli drone strike Friday on a car in the Tyre district town of Bazouriyeh killed a “prominent” Hezbollah military commander, Israeli media reports said.

Hezbollah meanwhile announced the death of three more of its fighters in the conflict, without mentioning where they were killed. It identified them as Ahmad Jawad Chehimi, 60, who hailed from the southern town of Markaba, Mustafa Ahmad Makki, 41, who hailed from the southern town of Tebnin, and Ibrahim Anis al-Zein, 42, who hailed from the southern town of Chhour.

The nun stood in front of a group of young students at a Lebanese Christian school and asked them to pray for the "men of the resistance" in southern Lebanon who she said were defending the country.

The men to whom nun Maya Ziadeh was referring are members of the Lebanese Shiite militant group Hezbollah, which has been clashing with Israel across a volatile border for nearly six months, becoming a critical regional player as the Israel-Hamas war persists in Gaza.

The White House has called on Israel and Lebanon to put a high priority on restoring calm after new deadly border crossfire and Israeli strikes targeting Hezbollah.

"Restoring calm along that border remains a top priority for President Biden and for the administration and it has to be of utmost importance, we believe, as well for both Lebanon and Israel," National Security Council spokesman John Kirby told reporters.

Hezbollah fired rockets with heavy warheads at towns in northern Israel, saying it used the weapons against civilian targets for the first time Thursday in retaliation for Israeli airstrikes the night before that killed nine, including what the group said were several paramedics.

There were no reports of Israelis hurt in the rocket attack, local media said. The Israeli military did not immediately offer comment on the rocket attack.

The U.N. peacekeeping force deployed in southern Lebanon along the border with Israel has calling for ending the escalation a day after exchanges of fire killed 17 people.

The force known as UNIFIL said it is very concerned over the surge of cross-border violence between the Israeli military and Lebanon-based militant groups including Hezbollah.

A war monitor said Israeli air strikes Friday on Syria's Aleppo province killed at least 42 including 36 Syrian soldiers, the deadliest toll for the Syrian army since the Israel-Hamas war began.

Israel has launched hundreds of air strikes in Syria since civil war there broke out in 2011, targeting army positions as well as Iran-backed forces including Hezbollah, an ally of Damascus and Palestinian militant group Hamas.

Kataeb Party chief Sami Gemayel on Thursday warned that “we are on the verge of repeating the Gaza experience in south Lebanon,” as he offered condolences over the civilians and paramedics who were killed by Israeli strikes over the past days.

The Israeli army will “enter into Lebanon” after finishing the Rafah operation, the Israeli Public Broadcasting Corporation has quoted an unnamed Israeli official as saying.