UPDATE: But see this report that the IDF general was out of contact with UNIFIL during the height of the incident.
I didn't post anything yesterday about the Israeli-Lebanese border clash because the conflicting narratives of the two sides made it unclear who provoked it. At least according to early reports, UNIFIL is supporting the Israeli claim that they were cutting trees in Israeli territory when the firefight began.
Which raises the question of why Lebanon might have provoked an outbreak, since there is enough fear of a renewed Israel-Hizbullah war without the Lebsanese Army provoking new tensions. This Ha'aretz article says the IDF blames a single Lebanese officer acting on his own initiative. That may well be the case, or it may be a convenient explanation that lets the Lebanese government off the hook and defuses a tense situation.
Lebanon disputes that the Blue Line, demarcated by the UN after Israel's withdrawal from Lebanon always represents the international border, and such a disagreement seems in play at the location where the trees were being cut, but the Lebanese have agreed to respect the Blue Line in the past.