Hackers threatened to cut power to London Olympics opening ceremony

London 2012 officials feared hackers might disrupt stadium's electricity supply as millions watched

London 2012 Olympics security officials have revealed the extent of the cyber attack threat to the opening ceremony, including the possibility of all the electricity at the stadium being turned off by hackers.

"There was a suggestion that there was a credible attack on the electricity infrastructure supporting the Games," Oliver Hoare, head of cyber security for the Olympics told the BBC, revealing that on the morning of the Olympic ceremony, he was told there was a "realistic threat" hackers could take down power to the stadium.

Hoare was later told that if electricity was cut during the opening ceremony, then lights could be back up and running in under 30 seconds. Nonetheless, he was still very much aware how embarrassing it would be for the UK if hundreds of millions of people worldwide witnessed the London 2012 Olympic opening ceremony suddenly immersed in darkness.

"Thirty seconds at the opening ceremony with the lights going down would have been catastrophic in terms of reputational hit," said Hoare. "So I watched the opening ceremony with a great deal of trepidation."

That was despite the number of tests the Olympic cyber security team carried out, with Hoare's team testing the electricity structure five times in the run-up to the big day.

Earlier this year, it was revealed how the Olympic security officials had to deal with six major cyber attacks during the course of the games.