An Israeli airstrike killed at least 356 people as it launched an attack on Lebanon, the country’s health ministry has said.

Aside from the deaths, more than 1,200 others were also injured in the attack, which has been considered the “deadliest” in the ongoing war.

Firass Abiad, the health minister, said thousands of families had also been displaced in Lebanon following the attack.

“The strikes by the Israeli enemy in southern Lebanon and the Bekaa and Baalbek in the east killed 356 people, including 24 children and 42 women, and injured 1,246,” said Mr. Abiad.

Lebanese state media also reported raids in the country’s east, even as Hezbollah said it targeted five sites in Israel.

An Israeli military spokesman, Daniel Hagari, said the country’s fighter jets had struck over 1,300 targets affiliated with Hezbollah, particularly in southern Lebanon and the Bekaa Valley.

As Israeli warplanes raced through Lebanon’s skies, Hezbollah launched its own barrage in a counterattack.

Air-raid sirens rang out repeatedly as roughly 165 rockets and other munitions crossed into Israeli territory, according to the Israeli military.

Most of the attacks were intercepted by Israel’s anti-missile defence system, and there were no reports of deaths or serious casualties.

Hezbollah has been firing rockets and drones at Israel since last October in support of its ally, Hamas, prompting Israeli counterattacks.

But Israel has ratcheted up its assaults on Hezbollah dramatically over the past week, raising fears that the current fighting could escalate into a full-scale war involving ground troops.

Prime Minister Benjamin Netanyahu of Israel told citizens to expect more “complicated days” ahead.

On Monday night, Israel conducted an airstrike in Beirut in an attempt to assassinate Ali Karaki, one of the members of Hezbollah’s top leadership.

Over the past several months, Israel has assassinated many senior commanders in Hezbollah.

On Friday, Israel’s air force killed Ibrahim Aqeel, another veteran leader, alongside several other senior commanders of the group’s elite commando unit, in a bombing on a residential building in Beirut that killed and wounded dozens.