A massive explosion and fire has rocked a port in southern Iran purportedly linked to a shipment of a chemical ingredient used to make missile propellant.

One maritime risk firm says it believes the affected containers held solid fuel for use in ballistic missiles.

Iranian authorities have said there was a “failure to observe safety principles” at the port of Bandar Abbas, where an explosion Saturday killed dozens of people, but testing is required to determine ...

The explosion occurred as Iran began a third round of nuclear talks with the United States, but there was no immediate indication of a link between the two events.