A spy device disguised as a rock reportedly exploded last month outside an Iranian facility that is believed to be a site used for nuclear weapons development.

Iran’s Revolutionary Guard troops were inspecting data and telephone links to the Fordo nuclear facility in August when they found the rock, tried to move it and saw it explode, intelligence sources told the Sunday Times, according to Al Arabiya.

The ‘rock’ was able to intercept computer data from the facility, the newspaper reported on Sunday, citing those who surveyed parts of the device after the explosion.

The U.N. and western powers suspect Iran’s nuclear program is intended for the creation of weapons, but Iran insists it is for peaceful purposes.

The Fordo facility, near Qoms, is currently enriching uranium to a level close to the amount used in nuclear weapons, the Associated Press reports.

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