LONDON: The electronic clock counting down the 500 days to the start of the 2012 London Olympics stopped on Tuesday in an embarrassing incident less than a day after it was unveiled in a glitzy launch. The steel clock made by Omega in London's Trafalgar Square ground to a halt at 500 days, seven hours, six minutes and 56 seconds, then began counting the wrong way before a technician arrived to repair it. Omega said in a statement: “We are obviously very disappointed that the clock has suffered this technical issue. “The Omega London 2012 countdown clock was developed by our experts and fully tested ahead of the launch in Trafalgar Square. Four British Olympic champions — rowers Pete Reed and Andy Hodge and sailors Iain Percy and Andrew Simpson — unveiled the clock Monday to mark the 500-day countdown to the opening ceremony.