It was one of the deadliest single strikes in an intensified air campaign against Hezbollah group.

The strike late Wednesday came as the United States and its allies called for an “immediate” 21-day cease-fire to “provide space for diplomacy.”

Israel has threatened to launch a ground invasion, and the increasingly heavy exchanges of fire could trigger an all-out war.

Lebanon's National News Agency said the strike occurred near the ancient city of Baalbek in Lebanon's northeastern Bekaa Valley, which runs along the Syrian border.

It quoted Ali Kassas, mayor of the village of Younine, as saying that the bodies of 23 Syrian citizens were pulled from under the rubble. He said four Syrians and four Lebanese were wounded.

Hussein Salloum, a local official in Younine, said most of the dead were women and children, and that rescue efforts lasted through the night and into Thursday morning.

“We dug through the rubble with our own hands” until a small bulldozer was brought in, Salloum told The Associated Press by telephone. “We had very limited capabilities.”

The Lebanese Red Cross said it recovered nine bodies, while others were recovered by Hezbollah group’s paramedic service and the Lebanese Civil Defense.

Lebanon, with a population of around 6 million, hosts nearly 780,000 registered Syrian refugees and hundreds of thousands who are unregistered — the world’s highest refugee population per capita.

Israel's military said it was carrying out new strikes against Hezbollah targets in Lebanon on Thursday, while Hezbollah said Thursday that it again targeted defence industry complexes in northern Israel near the city of Haifa.

"Defending Lebanon and its people", Hezbollah fighters "bombed the Rafael military industry complexes... with salvos of rockets", the group said in a statement, after announcing several previous targetings of the site since Sunday.

Israeli Prime Minister Benjamin Netanyahu, who is traveling to the United States for the U.N. General Assembly, has not yet responded to the cease-fire proposal.

But his foreign minister, Israel Katz, said Israel would continue fighting “with full force until victory.”

Hezbollah has also not yet responded to the proposal. The group has insisted it would only halt its strikes if there is a cease-fire in Gaza, which appears out of reach despite months of negotiations led by the United States, Egypt and Qatar.

Israeli strikes since Monday have killed more than 630 people in Lebanon, according to local health authorities, who say around a quarter were women and children. Several people have been wounded by shrapnel in Israel.

Israel struck 75 sites overnight across southern and eastern Lebanon, the military said. At least 45 projectiles were fired from Lebanon early Thursday, all of which were intercepted or fell in open areas, it said.