The Lebanese army filed an official complaint on Friday with the United Nations Interim Force in Lebanon (UNIFIL) over Israel’s incursion into sovereign territory, beyond the blue line — the UN-defined border between Israel and its northern neighbor.

According to Lebanese officials, Israeli engineers and contractors have crossed the border multiple times over the past few days in order to build a security barrier between the two countries.

The complaint alleged that several points of the six-meter-high barrier were between 30 and 65 cm closer to the pavement on the Lebanese side than originally agreed upon.

The Lebanese army has increased its troop presence and alert level in the area.

The IDF’s Spokesman’s Office issued a response stating that none of the construction crossed the international border and that the project was being done in full cooperation with UNIFIL.

Israel enjoys no diplomatic relations with Lebanon. The two nations have been in a state of war with one another for six decades.