Israel’s military said a Hezbollah drone killed four soldiers at one of its northern bases Sunday, as it expanded its bombardments of Lebanon and troops battled militants across the border.

The attack on a military training camp in Binyamina, near Haifa, was the deadliest such assault on an Israeli base since 23 September, when Israel increased its attacks on Hezbollah in Lebanon. Emergency services reported more than 60 wounded.

Authorities in Gaza, meanwhile, said the death toll from an Israeli strike Sunday on a school being used as a shelter for displaced people had risen to 15, including whole families, while a separate overnight strike on a hospital killed four.

And as fighting raged between Israel and Hezbollah forces in Lebanon’s south, United Nations peacekeepers said they had again been in the firing line.

They said Israeli troops “forcibly” entered a UN position with two tanks, after Israeli Prime Minister Benjamin Netanyahu called on the force to withdraw from the area.

Israel’s military said a tank had backed into the UN post while under fire.

Iran-backed Hezbollah said late Sunday that it launched “a squadron of attack drones” at the Binyamina camp, around 30 kilometers south of the major city of Haifa.

The strike was in response to Israeli attacks, including air strikes on Thursday that Lebanon’s health ministry said killed at least 22 people in central Beirut.

In a later statement, Hezbollah warned Israel that “what it witnessed today in southern Haifa is nothing compared to what awaits it if it decides to continue its aggression against our noble and dear people.”

An Israeli volunteer rescue service, United Hatzalah, said its teams in Binyamina assisted “over 60 wounded people” with injuries ranging from mild to critical.

Hezbollah has been firing rockets and drones into Israel for more than a year in support of Hamas militants in Gaza.

Since late September, however, its strikes have reached further into the country.

Israel’s sophisticated air defenses have intercepted most of the projectiles, with few casualties caused by strikes or falling debris. Its recent strikes have increasingly focused on areas beyond Hezbollah’s traditional strongholds in southern Beirut, and Lebanon’s south and east.

Israel said its air force hit “Hezbollah launchers, anti-tank missile posts, weapons storage facilities” and other targets, while on the ground its soldiers “eliminated dozens” of fighters.

Lebanon’s official National News Agency said Israeli forces had “escalated their attacks” on southern Lebanon with “successive air strikes” pounding several border villages.

It later reported that an Israeli strike on Mayfadoun, near Nabatiyeh, in southern Lebanon, had killed five people and wounded one other.

Hezbollah said its forces clashed several times with Israeli troops who tried to “infiltrate” villages along the border.

Before the drone strike it had said it launched a salvo of rockets at a “base in southern Haifa.”

The group later aired an audio recording of its slain leader Hassan Nasrallah calling on fighters to “defend this holy and blessed land and this honorable people.”

Nasrallah was killed in an Israeli air strike in south Beirut on 27 September and several other senior commanders of the movement have also been killed.

Israel’s military said about 115 projectiles fired by Hezbollah had crossed into Israeli territory by Sunday afternoon.

A Hezbollah fighter was captured emerging from a tunnel in south Lebanon on Sunday, Israel’s military said, the first such announcement since the start of the ground offensive.

UN peacekeepers accused Israeli troops of breaking through a gate and entering one of their positions before dawn Sunday in south Lebanon, the latest of several incidents the UNIFIL mission has reported since Thursday.

Five Blue Helmets have so far been injured, provoking international condemnation.

“Two IDF (Israeli military) Merkava tanks destroyed the position’s main gate and forcibly entered the position” in the Ramia area, before leaving 45 minutes later, UNIFIL said.

The Israeli military later said a tank “backed several meters into a UNIFIL post” while “under fire” and attempting to evacuate injured soldiers.

Earlier Sunday, Netanyahu had called on the UN to move peacekeepers in southern Lebanon out of harm’s way, after the mission rejected requests to abandon its positions.