Israel is expected to launch airstrikes inside Lebanon in response to a deadly explosion near its northern border that killed one person and injured about 20 others, Al Hadath reported, citing sources.

The blast occurred near the Israeli town of Neot Mordechai in the Upper Galilee, close to the Lebanese border, while a group of students and teachers from a religious school were on an annual school trip. Israeli emergency services said one person was killed and around 24 others were injured, including some in serious condition.

The precise circumstances of the explosion remained unclear. Police said preliminary indications suggested it was caused by unexploded ordnance, while Israeli media reported that someone may have touched the explosive object and possibly placed it in a bag before it detonated.

Israeli media outlet Walla reported that the explosion appeared to have been caused by an old rocket fired by Hezbollah, the Iran-backed Lebanese group. The outlet also said the military and police had previously declared the area clear of explosives.

The Israeli military said the circumstances of the incident were under investigation and that troops had been deployed to the scene to provide assistance. Military spokeswoman Ella Waweya said in a post on X that forces were responding to reports of an explosion in northern Israel.

Israel’s national emergency medical service, Magen David Adom, said paramedics treated the injured at the scene. According to Israeli news outlet Ynet, 14 ambulances and three rescue helicopters were dispatched to the area.

Magen David Adom said eight people were being treated for moderate to serious injuries, while several others had sustained minor wounds. The service described the incident as complex and said the injured would be transferred to hospitals as soon as possible.

Israeli authorities described the explosion as a serious incident. Prime Minister Benjamin Netanyahu’s office said he had been briefed on reports about the blast. Netanyahu also interrupted a live social media broadcast related to the election following the incident.

Meanwhile, Lebanese authorities were monitoring developments through Israeli media reports, a Lebanese military source told Arab News.

“There is no Lebanese army presence near the site of the incident, and we do not know whether it occurred inside Lebanese territory occupied by Israel or outside it,” the source said. “We are monitoring what Israeli media are reporting.”

The location of the explosion and the circumstances surrounding it had not been independently established in the available reports.