Denies involvement in Sony hack

North Korea denies that it was involved in the Sony hack. North Korea calls for a joint investigation into the incident with the United States. North Korean spokesman:

We propose to conduct a joint investigation with the U.S. in response to groundless slander being perpetrated by the U.S. by mobilizing public opinion. If the U.S. refuses to accept our proposal for a joint investigation and continues to talk about some kind of response by dragging us into the case, it must remember there will be grave consequences.