Antonio Guterres' condemnation of the explosion was highlighted in a statement from his spokesperson's office that emphasized the need to ensure the safety and security of peacekeepers at all times.
"The situation along the Blue Line between Lebanon and Israel since 8 October last year, with daily exchanges of fire between non-state armed groups based in Lebanon and the Israel Defense Forces, continues to be of grave concern," it said.
The statement expressed "grave concern" for the escalating violence along the Blue Line and urged parties to "refrain from further breaches of the cessation of hostilities."
Earlier Saturday, at least one civilian and three soldiers from the UN Interim Force in Lebanon (UNIFIL) were injured in an Israeli raid that targeted their vehicle in the south of the country, according to media reports.
UNIFIL expressed concern “over the surge of violence across the Blue Line right now.”
The Israeli army denied that it targeted any UNIFIL vehicle in the Rmeish area in southern Lebanon.
Tension has flared along the border between Lebanon and Israel amid intermittent exchanges of fire between Israeli forces and Hezbollah, in the deadliest clashes since the two sides fought a full-scale war in 2006.
The border tension comes amid an Israeli military offensive in the Gaza Strip that has killed more than 32,700 people following a cross-border attack by the Palestinian resistance group, Hamas, on Oct. 7.