The IDF said it responded with artillery fire after an anti-tank missile was fired from Lebanon.
A statement said that some parts of the missile “fell in Lebanon, and some of its parts fell near the fence in the town of Ghajar in Israeli territory.”
The official Lebanese news agency reported that more than 15 Israeli shells landed on the outskirts of the Lebanese villages of Kafr Shuba and Halta.
No armed group has so far claimed responsibility for the missile launch.
The United Nations peacekeeping force in Lebanon (UNIFIL) urged all parties to “exercise restraint and avoid any action that could lead to further escalation” on the border, where tensions have escalated in recent months.
In April, the Israeli military launched airstrikes against targets it said belonged to the Palestinian Islamic Resistance Movement (Hamas) in southern Lebanon after more than 30 rockets were fired from there into Israeli territory.
It was the largest such barrage from Lebanon since Israel and the Lebanese group Hezbollah went to war in 2006.
UNIFIL said its peacekeepers detected explosions near Majidieh shortly after 08:00 local time (05:00 GMT) on Thursday, and while they could not confirm the cause, the sounds were consistent with a possible missile launch.
It added that at approximately 12:00 noon, they detected the firing of Israeli shells that hit Kafr Shuba.
There were no immediate reports of damage or injuries.
Security sources in Lebanon told the Reuters news agency that two missiles – not an anti-tank missile – were fired towards Israel.
The Israeli military initially said that a missile “exploded near the Blue Line in Israeli territory,” referring to the UN-drawn border between the two countries.
But it later said that after evaluating the shrapnel, the projectile was identified as an anti-tank missile, and that some of its parts fell inside Israeli territory near the village of Ghajar.
Israel currently occupies both halves of Ghajar and was supposed to withdraw from the Lebanese half under the UN Security Council resolution that ended the 2006 war.
Hezbollah did not comment on the rocket fire. However, on Thursday morning, the Iranian-backed group issued a statement condemning the “serious measures” recently taken by Israeli forces in the village of Ghajar, including “the erection of barbed wire and the construction of a concrete wall surrounding the entire town.”
Last month, Israel filed a complaint with the United Nations saying Hezbollah had set up two tents a few meters above the border on Israeli territory in the area.
Israeli media reported on Sunday that the group had dismantled one of the tents, amid mounting international pressure.
Thursday’s exchange of fire also comes a day after Israeli forces completed a major operation in the Jenin refugee camp in the occupied West Bank.
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