Four Israeli soldiers were killed in a drone attack by Hezbollah on an army base in central Israel on Sunday while seven others were severely wounded, said the military.
The Lebanon-based armed militant group called the attack near Binyamina city retaliation for Israeli strikes on Beirut on Thursday that killed 22 people, reported CBS News.
Later, it said it targeted Israel's Golani Brigade, launching dozens of missiles to occupy Israeli air defence systems during the assault by "squadrons" of drones.
As many as 61 people were injured in the attack, according to Israel's national rescue services. This is the second time in two days that Israel has come under a drone attack. On Saturday, a drone struck a suburb of Tel Aviv during the Jewish holiday of Yom Kippur, casing damage but no injuries.
The strike on Sunday came the same day when the United States announced it would deploy an anti-missile THAAD system to Israel to help bolster its protection against missiles.
Earlier on Sunday, Israeli Prime Minister Benjamin Netanyahu called on the United Nations peacekeepers to heed the Israeli military's warnings to evacuate Lebanon immediately as the fighting intensified.
Israel has been firing on posts where first responders and UN peacekeepers were present since the beginning of the ground operation against Hezbollah. The Israeli forces have blamed Hezbollah for ferrying fighters and weapons in ambulances.
It has also claimed that the Iran-backed militant group was operating in the vicinity of the peacekeepers, without providing evidence.
Meanwhile, the Lebanese Red Cross said paramedics were searching for casualties in the wreckage of a house destroyed by an Israeli airstrike in southern Lebanon when a second strike left four paramedics with concussions and damaged two ambulances.