Two people died in an explosion that ripped through an explosive material production unit at a nuclear facility near Tehran, according to Iranian press reports on Monday.
The incident occurred at the Parchin military compound, located south-east of the Iranian capital, which UN nuclear inspectors have been seeking to visit to answer concerns about Iran’s atomic programme.
Reports said the blast was so powerful it shattered windows up to 12 kilometers away and the glare from the explosion lit up the night sky.
Israel in the past has said that Iran has used its Parchin military base as the site for secret tests of technology that could be used only for detonating a nuclear weapon.
Tehran has denied IAEA (The Vienna-based International Agency for Atomic Energy) inspectors access to Parchin since 2005. In August Iran reiterated that it will not allow IAEA inspectors to visit the site.
In a recent statement, Israeli Intelligence Minister Yuval Steinitz said internal neutron sources such as uranium were used in nuclear implosion tests at Parchin.
Israel, his statement said, based its information on "highly reliable information," without elaborating.