Iran says a fire at a military facility south of Tehran has killed two workers.
The state news agency IRNA quotes Iran's Defense Industries Organization as saying the fire broke out on the evening of October 5 but gave no further details.
An Iranian opposition website, Saham, described the incident as a strong explosion near the Parchin military facility, around 30 kilometers southeast of the capital.
It did not give a source for its report, which could not be independently verified.
The UN nuclear watchdog agency suspects Iran may have carried out explosives tests at Parchin around a decade ago that could be relevant for any attempt to develop a nuclear weapons capability.
The International Atomic Energy Agency (IAEA) wants to visit a specific location at the site, but Iran has so far not granted access.