Senior political figures in Iran say the Islamic Republic has fully mastered the Stuxnet computer worm and it poses no threat of any kind, although an Iranian computer techie says the worm is spreading and still poses a serious problem. Stuxnet, which has targeted industrial control systems in Iran and many other countries, was found on the personal computers of staff members of the nuclear plant in Bushehr, officials have announced. But beyond that, no one wants to say where Stuxnet has gone and what it has done.