Four soldiers were wounded, one of them seriously, in a blast on the Lebanon border overnight, the Israel Defense Forces said Monday morning. The Lebanese Hezbollah terror group took responsibility for the explosion, saying it occurred as troops crossed the border.

The cause of the blast that wounded the soldiers in the western region of the border with Lebanon was under investigation by the military, which said in a statement that the explosion was of “unknown origin.”

The military said the incident took place during “operational activity” carried out by troops of the Golani Brigade’s reconnaissance unit and the elite Yahalom combat engineering unit.

One soldier was seriously wounded, two were listed in moderate condition, and another was lightly hurt, according to the IDF. The troops were taken by helicopter to a hospital.

Claiming the blast, Hezbollah said it placed several explosive devices adjacent to the border, inside Lebanese territory, in an area across from the northern Israeli community of Adamit.

The terror group said the bombs were detonated as the Israeli troops crossed the frontier.

Also overnight, the IDF said fighter jets struck Hezbollah sites in southern Lebanon.

The targets included rocket launch posts, buildings used by the terror group, and other infrastructure in Seddiqine, Matmoura, Labbouneh, and Ayta ash-Shab, according to the military.

Troops also shelled areas near Ayta ash-Shab with artillery to “remove threats,” the army added.

Since October 8, Hezbollah has attacked Israeli communities and military posts along the border on a daily basis with rockets, drones, anti-tank missiles and other means, saying it is doing so to support Gaza amid the war there. The group is an Iranian proxy in Lebanon, and Palestinian terror groups Hamas and Palestinian Islamic Jihad are backed by Iran.

Israel has threatened to go to war to force Hezbollah away from the border if it does not retreat and continues to threaten northern communities, from where some 70,000 people were evacuated to avoid the fighting.

So far, the skirmishes on the border have resulted in eight civilian deaths on the Israeli side, as well as the deaths of 10 IDF soldiers and reservists. There have also been several attacks from Syria, without any injuries.

Hezbollah has named 274 members who have been killed by Israel during the ongoing skirmishes, mostly in Lebanon, but some also in Syria. In Lebanon, another 53 operatives from other terror groups, a Lebanese soldier, and at least 60 civilians have been killed.