The Israeli military on Monday said its own artillery fire killed an Israeli civilian a day earlier near the northern border with Lebanon, where its forces are fighting Hezbollah.
After opening an investigation, the military said "the initial findings suggest that the Israeli civilian was killed by IDF artillery fire conducted to support IDF soldiers operating in southern Lebanon".
"Several severe issues and operational errors took place during the incident, including both the planning and execution of the fire," it added.
Lebanon's Iran-backed Hezbollah militant group said it attacked soldiers in northern Israel's Misgav Am on Sunday, where first responders said rocket fire from Lebanon killed one person.
Israel's military later said it was investigating whether its own fire had killed a civilian in the same area.
On Monday, it said the artillery fire that killed Ofer Moskovitz "was carried out at an incorrect angle and did not follow required protocols".
"As a result, five artillery shells were fired at the Misgav Am ridge instead of toward the enemy target," a military statement said, expressing regret over the incident and extending "its deep condolences to the Moskovitz family and the Misgav Am community at this difficult time".
Lebanon was pulled into the Middle East war when Hezbollah began firing rockets into Israel on March 2 to avenge the killing of Iran's supreme leader Ali Khamenei in Israeli-US attacks.
Israel has sent troops into Lebanon and carried out extensive airstrikes in the country, while Hezbollah continues to fire rocket barrages across the border.