The explosion which occurred in the vicinity of the city of Natanz in central Iran province of Isfahan a few minutes ago has nothing to do with the nuclear facilities there, a local official told IRNA on Saturday night.
The sound of a huge explosion was heard in the sky of the vicinity of the city of Natanz.
The explosion seemingly happened in "Badrood" about 20 kms to Ahmadi Roushan nuclear complex.
According to the official, the explosion had no tolls.
More investigations were underway, he said, adding the explosion occurred 20:15 local time (18:47 hours GMT) in the sky and as such is not connected with the nuclear facilities there.
No clashes happened in the sky and the sound was due to a single shot by defense systems, he added.
Earlier, the city's governor had told IRNA that security officials were investigating the issue.
According to the latest reports, a defense missile was fired to test the performance of rapid reactions units and then exploded in the sky according to a pre-planned scheme.
An eye witness told that people heard the sound of the explosion and simultaneously saw a light which they thought was from an explosion of a an object up in the sky.
Exact details of the explosion are not clear yet.