<p>The hacker also disabled the House of Commons telephone system, the Daily Mail reported.<br />Claire Perry, Tory MP for Devizes in Wiltshire, 117 km from London, said she found her voicemail had been changed.<br /><br />"There was a general, system-wide failure overnight. But the changing of the voicemail strongly suggests that the two things were linked, and that a good deal of planning had gone into the operation," she said. She, however, did not say what the message was.<br /><br />David Whitelegg, an IT security expert, said the hacker may not have been a prankster, but that he may have been testing the security of the system.<br /><br />"It's worrying because it is the sort of thing a terrorist could do prior to launching an offensive. It shows our vulnerability to a cyber attack," he said.</p>
<p>The hacker also disabled the House of Commons telephone system, the Daily Mail reported.<br />Claire Perry, Tory MP for Devizes in Wiltshire, 117 km from London, said she found her voicemail had been changed.<br /><br />"There was a general, system-wide failure overnight. But the changing of the voicemail strongly suggests that the two things were linked, and that a good deal of planning had gone into the operation," she said. She, however, did not say what the message was.<br /><br />David Whitelegg, an IT security expert, said the hacker may not have been a prankster, but that he may have been testing the security of the system.<br /><br />"It's worrying because it is the sort of thing a terrorist could do prior to launching an offensive. It shows our vulnerability to a cyber attack," he said.</p>