@Frank Apisa,
Hezbollah's media office told Al Jazeera the explosion was caused by a "technical error" at their arms depot.
"This explosion was at a house that stored weapons - result of technical error. No one was killed or injured. The building belonged to a Hezbollah affiliated de-mining association." (Al Jazeera, reporting from Beirut.)
Four casualties now, according to the 'Daily Star'.