A computer virus which could spark a global doomsday may have fallen into terrorists' hands, The Sun reported on Tuesday.
Stuxnet, dubbed the world's first cyber super-weapon, is thought to have been used to cripple Iranian President Mahmoud Ahmadinejad's nuclear programme.
But now it is feared Iranians have discovered the deadly bug and are planning revenge attacks using terror networks, the newspaper said citing scientists.
The "worm" virus can cripple computers running everything from traffic lights to the electricity grid. It can even stop water flowing to taps.
Virus expert Ralph Langner - who recently warned US leaders about the threat - said: "There's now no way we can stop the proliferation of cyber-weapons."
"Rogue states and terrorists will soon be able to use them."