VIENNA (Reuters) - A U.S. security institute said it has located via satellite imagery a section of a sprawling Iranian military complex where it said an explosion or fire might have taken place earlier this week.
Iran's official IRNA news agency on Monday cited an Iranian defence industry body as saying that two workers were killed in a fire at an explosives factory in an eastern district of Tehran.
Iran's Defence Industries Organisation said the fire broke out on Sunday evening, IRNA said, giving no further detail.
An Iranian opposition website, Saham, described the incident as a strong explosion that took place near the Parchin military complex around 30 km southeast of the capital. It did not give a source and the report could not be independently verified.
In Paris, a spokesman for an exiled Iranian opposition group said an explosion occurred late on Sunday in a chemical industry unit in Parchin that deals with the production of gunpowder and that at least four people were killed.
The dissident National Council of Resistance of Iran (NCRI) exposed Iran's uranium enrichment plant at Natanz and a heavy water facility at Arak in 2002. But analysts say it has a mixed track record and a clear political agenda.
The Washington-based Institute for Science and International Security (ISIS) said it had obtained commercially available satellite imagery on which six buildings at Parchin appeared damaged or destroyed.
However, the images ISIS issued indicated the site of the possible blast was not the same location in Parchin where the U.N. nuclear agency suspects that Iran, possibly a decade ago, carried out explosives tests that could be relevant for developing a nuclear arms capability. Iran denies any such aim.
The U.N. International Atomic Energy Agency wants to visit this area of Parchin, but Iran has so far not granted access. Iran says Parchin is a conventional military facility and that its nuclear programme is entirely peaceful. It has often accused its enemies of seeking to sabotage its atomic activities.
ISIS said its analysis of the satellite imagery from Oct. 7 and 8 indicated an explosion could have taken place at a southern section of Parchin.
"Several signatures that coincide with those expected from an explosion site are visible here," it said on its website.
"Two buildings that were present in August 2014 are no longer there, while a third building appears to be severely damaged. In total at least six buildings appear damaged or destroyed," ISIS added.
Israel and the United States have not ruled out military action against Iran if diplomacy fails to resolve a decade-old dispute over Tehran's nuclear programme. Israel is widely believed to be the Middle East's only nuclear-armed power.
(Reporting by Fredrik Dahl; additional reporting by John Irish in Paris; Editing by Dominic Evans)