Hezbollah guerrillas have secretly stockpiled rockets and other arms in southern Lebanon, Israel said on Wednesday, citing as proof the explosion of a suspected cache in the U.N.-patrolled truce zone, Reuters reported.
Tuesday morning's blast hit a Hezbollah arsenal in the village of Khirbet Selim, near the Israeli border, a Lebanese security source said. It was not clear how old the ordnance was.
Hezbollah had no comment on the incident. UNIFIL, the U.N. peacekeeper force that was beefed up after Israel and Hezbollah fought a 2006 war in south Lebanon, said it and the Lebanese army were investigating.
Israel has accused Iranian and Syrian-sponsored Hezbollah of rearming in the former battlegrounds, a violation of the U.N. Security Council ceasefire resolution. Israel has itself been in breach by continuing military overflights of the area.
Briefing reporters, an Israeli military official said the blast had rocked the area and destroyed a building.
Denying knowledge of what had caused the explosion, the official described the site as "one of dozens of ammunition and rocket storage (sites) in south Lebanon".
Hezbollah quickly cordoned off the blast site and took items away, the Israeli official said.
"The Lebanese army let Hezbollah manage this event and (did) not help UNIFIL do its job in the area".
"Even if the UNIFIL forces want to go somewhere, the Hezbollah forces do not let them do so. There is a kind of understanding among all the forces that everyone knows who is the strong one," the official said.
Asked about the incident, UNIFIL said it was investigating.
"Yesterday we couldn't access the area because of security reasons. The area was not safe enough because there was still a potential risk of fire or explosion. But we cordoned off the area and this morning we were able to access the area," said a UNIFIL spokesman, Andrea Tenenti.
"From preliminary information that we have, the incident was an explosion caused by a deflagration of ammunitions."
UNIFIL later said in a statement it considered the incident a serious violation of Security Council resolution 1701 stating that there should be no unauthorized weapons between the Litani River and the Blue Line.
That resolution ended the 2006 war between Israel and Hezbollah guerrillas.
The Lebanese army said in a statement it had secured the area after the explosion, which it described as having taken place in a deserted building in Khirbet Selim.
Prime Minister-designate Saad al-Hariri's U.S.-backed coalition secured a victory in Lebanon's June 7 parliamentary election.
Hariri has been holding talks over the shape of the new government which is expected to group his "March 14" alliance, backed by countries like Saudi Arabia, with rivals including Hezbollah.