The head of Lebanon's customs authority was formally arrested on Monday after being questioned over the massive explosion in Beirut earlier this month, the state-run National News Agency reported.
The investigation is focused on why nearly 3,000 tons of explosive ammonium nitrate was being stored at the city's port. The ignition of the stockpile caused an explosion that tore through the capital, killing at least 180 people and wounding 6,000.
Thirty people are still missing after the Aug. 4 blast, which caused an estimated $10 billion to $15 billion in damage.