solid fuel

Iran's defence ministry denied reports that the explosion was caused by the improper handling of a shipment of sodium perchlorate, a solid fuel used for ballistic missiles.

Ambrey Intelligence, a private maritime risk consultancy, said it believed that intense fires that could be seen spreading between containers before the explosion were a result of "improper handling of a shipment of solid fuel intended for use in Iranian ballistic missiles".

The firm said it believed the affected containers had contained solid fuel destined for ballistic missiles, and was aware that an Iran-flagged ship "discharged a shipment of sodium perchlorate rocket fuel at the port in March 2025".

The New York Times quoted a person with ties to Iran's Islamic Revolutionary Guard Corps, speaking on condition of anonymity, as saying that what exploded was sodium perchlorate - a major ingredient in solid fuel for missiles.

During the first three minutes, three solid fuel rocket motors power the missile’s flight.