More fantasy tales have emerged from the US http://www.bbc.co.uk/news/technology-30879637
The US knew North Korea was behind the Sony Pictures hack because it had secretly infiltrated the country's computer networks in 2010, according to the New York Times and Der Spiegel.
The newspapers cited US officials and leaked documents from the National Security Agency.
The New York Times said hidden software had alerted US intelligence services to North Korean hacking activity.
North Korea has consistently denied involvement in the security breach.
This is the third story change so far, its becoming a running joke.