Israel said on Monday that it has uncovered a Hezbollah military outpost on the southern Lebanese border. A senior officer from the militarys Northern Command told reporters that the armed party had set up the post under the guise of an environmental advocacy group. The new observation post in the village of Al-Adisa violates the United Nations Security Council resolution 1701 that ended the 2006 Israel-Hezbollah war and bars militant activity in southern Lebanon, he added on condition of anonymity under military guidelines. He said Hezbollah is using a tree-planting campaign by the "Green Without Borders" association as a cover for its activity along the border to gather intelligence on Israeli troops. The Lebanese non-governmental organization has acknowledged its affiliation with the party, but claims its purpose on the border is purely environmental. The Israeli officer said the army discovered five other Hezbollah posts in 2017, in breach of the UN agreement. "We havent seen any Hezbollah arms yet, but we can see military infrastructure and its clear this is part of extensive activity in south Lebanon and in Lebanon in general that is a threat to Israel," the officer said. "This is of course a buildup that we cannot tolerate." The Israeli military on Monday released photos of what it said were the Hezbollah observation posts. One photo showed a uniformed man peering through a window with high-tech binoculars. Andrea Tenenti, a spokesman for the UN Interim Force in Lebanon (UNIFIL), said the peacekeeping force has "not observed any unauthorized armed persons" at the position and "continues to monitor activities closely," including those of the environmental group. The Israeli-Lebanon border, though tense, has been mostly quiet in recent years under UN supervision. Israel and Hezbollah fought a devastating month-long war in 2006, which ended in a stalemate.