The Israeli military said it intercepted an "aerial target" that crossed from Lebanon on Thursday, in an incident that jolted the calm prevailing at the frontier since the Palestinian group Hamas and Israel agreed a temporary truce.

Reuters witnesses heard blasts along the southeastern Lebanese frontier. There were no immediate claims of responsibility for any attacks from Lebanon.

Israel and the Iran-backed Lebanese group Hezbollah, a Hamas ally, had been trading fire across the border for weeks following the eruption of the Hamas-Israel war on Oct. 7, in the worst Israel-Hezbollah fighting since a 2006 war.

Other groups, including Hamas and the Palestinian group Islamic Jihad, also launched attacks from Lebanon against Israel during the conflict.

The Israeli army said on Thursday it had "successfully intercepted a suspicious aerial target that crossed from Lebanon into Israeli territory."

A spokesperson for the U.N. peacekeeping force in Lebanon (UNIFIL) told Reuters a launch was detected from Lebanon towards Israel, followed by Israeli retaliation.

At about 5 pm (1500 GMT) local time, shells landed in the vicinity of Marwahin, a village in south Lebanon on the border with Israel, according to a UNIFIL spokesperson. The shells landed a few hundred meters from a UNIFIL base and there was no damage to the base, he said.

The Israeli army did not immediately respond to a comment request.

Israel and Hamas struck a last-minute agreement on Thursday to extend their ceasefire for a seventh day, and Washington said it hoped the truce could be extended further to free more hostages and let aid reach Gaza.