Caretaker Prime Minister Hassan Diab.
Photo: AFP / HO / Dalati and Nohra
Judicial sources said the four would be questioned next week about warnings they received over the unsafe storage of ammonium nitrate in a warehouse.
Diab said his conscience was clear and expressed surprise at the charges.
He and his cabinet resigned days after the explosion, which he blamed on what he called a system of corruption. bigger than the state .
The disaster compounded a deep economic crisis in Lebanon that has led to hundreds of thousands of people taking to the streets to demand the removal of a political elite that they accuse of graft, mismanagement and negligence.