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Sony Pictures spokeswoman Jean Guerin declined comment on the U.S. official's remark ahead of the Christmas Day release of 'The Interview'' in the United States and Canada.
People familiar with probes by both the U.S. government and Sony have previously told Reuters that Pyongyang is the primary suspect. They believe the attack was retribution for backing of 'The Interview,'' a comedy about a CIA assassination attempt on North Korean leader Kim Jong Un.
A second U.S. government official told Reuters the National Security Division of the Department of Justice is involved in the hacking probe, which is a signal that the authorities are actively investigating whether 'state actors'' could be behind the attack.
Watch more: 2015: Major cyber-attacks ahead
To be sure, U.S. officials say that while North Korea is a leading suspect, they are continuing to investigate the case and have reached no final conclusion.
John Carlin, assistant attorney general for the National Security Division, said on Tuesday at an event sponsored by online subscription service Bloomberg Government, that Sony was closely cooperating with the Justice Department investigation.
'It has our full attention and we'll continue to work, cooperatively and in partnership, with Sony,'' he said.
Read More Hollywood in crisis mode over Sony scandal
Hackers infected the studio's network with software that wiped hard drives of Windows computers, preventing them from booting up.
They also stole vast quantities of data, then leaked sensitive documents on the Internet. Those documents included private emails in which executives made irreverent comments about celebrities and U.S. President Barack Obama, prompting the studio to issue public apologies.
Entities 0 Name: U.S. Count: 5 1 Name: Sony Count: 4 2 Name: Reuters Count: 2 3 Name: Canada Count: 1 4 Name: United States Count: 1 5 Name: CIA Count: 1 6 Name: Bloomberg Government Count: 1 7 Name: John Carlin Count: 1 8 Name: Robert Marquardt Count: 1 9 Name: Getty Images Sony Pictures Count: 1 10 Name: North Korea Count: 1 11 Name: Justice Department Count: 1 12 Name: North Korean Count: 1 13 Name: Barack Obama Count: 1 14 Name: Jean Guerin Count: 1 15 Name: Pyongyang Count: 1 16 Name: National Security Division of the Department of Justice Count: 1 17 Name: Kim Jong Count: 1 18 Name: National Security Division Count: 1 Related 0 Url: http://ift.tt/1whUBEi Title: Sony Pictures hack: the whole story Description: This has been a wretched year for big corporations in the US: Target, Home Depot, JPMorgan and, most recently, Sony Pictures have all had to deal with unauthorized security breaches over the past few months.
