The UN peacekeeping forces on the Israel-Lebanon border, known as UNIFIL, announced Monday that two of the four previously discovered Hezbollah tunnels cross the Blue Line – the border of Israel's withdrawal from Lebanon in 2000 – in violation of UN Security Council resolution 1701, which ended the 2006 Second Lebanon War.

"UNIFIL has requested the Lebanese authorities to ensure urgent follow-up actions in accordance with the responsibilities of the Government of Lebanon pursuant to resolution 1701," an official statement read.

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The Lebanese military declared a state of high alert on Monday where Lebanese soldiers prevented Israeli soldiers from unrolling a barbed wire fence in south Lebanon, according to Lebanese reports and a video distributed.

An argument reportedly ensued between the soldiers from the two countries near the village of Meiss Ej Jabal before the UN peacekeeping forces, also known as UNIFIL, intervened, separating the sides. The Lebanese objected to the Israelis' placing the fence on the border without the presence of the Lebanese military's geographic team.

According to Haaretz's Amos Harel, Israel has now reached the explosive stage in the operation against Hezbollah tunnels.

Lebanese army patrols have been facing Israeli forces in the areas where the latter is digging near the border. In particular, tension is rising in those enclaves where the IDF is operating: areas north of the border fence over which Israel claims sovereignty according to a UN decision.

In these areas there is no wall or fence separating the Israeli and Lebanese forces. In some places, the IDF has stretched barbed wire to mark the exact location of the border.

The Israeli soldiers ended up agreeing to move the fence behind the Blue Line to the Israeli side. The Israeli army confirmed that soldiers placed the fence near the blue line in coordination with UNIFIL in Lebanon. According to the military, the incident passed without violence.

The Israeli army said on Sunday that it found a Hezbollah attack tunnel crossing from Lebanon into Israel last week, the fourth discovered in recent weeks. The discovery of a third tunnel crossing into Israeli territory was announced on Tuesday by the Israeli army, a week after Israel launched Operation Northern Shield, aimed at destroying cross-border tunnels constructed by Hezbollah.