Four soldiers have been killed and more than 60 other people injured in a drone strike targeting an army base in northern Israel, the Israel Defence Forces (IDF) has said.
The IDF added seven soldiers had been severely injured in the attack on a base "adjacent to Binyamina" - a town around 20 miles (33km) to the south of Haifa.
Hezbollah has claimed responsibility for the attack, which it said targeted a training camp of the Israeli Defence Forces' (IDF) Golani Brigade in the area, which is based between Tel Aviv and Haifa, reports BBC.
The armed group's media office said the strike was in response to Israeli attacks in southern Lebanon and Beirut on Thursday.
The group said it targeted the camp in northern Israel using a "swarm of drones".
The Israeli ambulance service, Magen David Adom (MDA), said 61 people had been injured in the attack - including three critically. It added 37 of them had been taken to eight regional hospitals, either by ambulance or helicopter.
In a statement before the IDF confirmed the deaths, MDA said that alongside the three critically injured, 18 of the victims were in a moderate condition, 31 sustained mild injuries and nine people were "suffering anxiety".
The reason for the discrepancy in the number of critical injuries between MDA and the IDF is not clear.
Israeli censorship rules had initially prevented media outlets reporting exactly where or what was targeted, before the IDF confirmed it was the Binyamina base.
Some Israeli media outlets have reported the base was hit by a low-level drone launched from Lebanon - a relatively unsophisticated weapon that appears not to have activated early-warning alarms.
Throughout the evening, television bulletins, social media posts and online reports showed footage of emergency vehicles, including helicopters, taking casualties to hospitals across northern Israel.
Many of the wounded have been evacuated to Hillel Yaffe Medical Centre in nearby Hadera - with others being taken to hospitals in Tel Hashomer, Haifa, Afula and Netanya.
Details are still scarce but many of the injured appear to have been in a communal canteen at the time and were caught completely by surprise. Images circulating on social media appear to show an empty mess hall with a hole in the roof.