North Korea demands joint inquiry into Sony hack

North Korea on Saturday proposed a joint investigation with the U.S. into the hacking of Sony Pictures Entertainment, warning of "serious" consequences if Washington rejects a probe that Pyongyang says will prove it had nothing to do with the cyberattack.

U.S. officials blame North Korea for the hacking, citing the tools used in the Sony attack and previous hacks linked to the North, and have vowed a response. The break-in resulted in the disclosure of tens of thousands of confidential Sony emails and business files, and escalated to terrorist threats that caused Sony to cancel the Christmas Day release of the movie "The Interview." The comedy is about a plot to assassinate North Korean leader Kim Jong-Un.

On Saturday, an unidentified Foreign Ministry spokesman in Pyongyang said North Korea knows how to prove it's not responsible for the hacking, saying Washington is slandering Pyongyang by spreading unfounded rumors.

"The U.S. should bear in mind that it will face serious consequences in case it rejects our proposal for joint investigation and presses for what it called countermeasures while finding fault with" North Korea, the spokesman said in a statement carried by Pyongyang's official Korean Central News Agency, or KCNA.

"We have a way to prove that we have nothing to do with the case without resorting to torture, as what the CIA does," he said, adding that the U.S. lacks any specific evidence tying North Korea to the hacking.

A spokesman for the White House National Security Council rejected North Korea's proposal of a joint investigation.

"The government of North Korea has a long history of denying responsibility for destructive and provocative actions," he said. "If the North Korean government wants to help, they can admit their culpability and compensate Sony for the damages this attack caused."

Koh Yu-hwan, a professor at Seoul's Dongguk University, called the North's proposal a "typical" tactic the country has taken in similar disputes with rival countries. In 2010, North Korea proposed a joint investigation after a South Korea-led international team concluded that the North was behind a torpedo attack that killed 46 South Korean sailors, though Pyongyang denied its involvement. South Korea rejected the North's offer for the joint probe.

"They are now talking about a joint investigation because they think there is no conclusive evidence," Koh said. "But the U.S. won't accede to a joint investigation for the crime."

On Friday, President Barack Obama declared that Sony "made a mistake" in shelving the satirical film about a plot to assassinate the North Korean leader, and pledged that the U.S. would respond "in a place and manner and time that we choose" to the hacking attack on Sony that led to the movie's withdrawal.

"I wish they had spoken to me first. ... We cannot have a society in which some dictator someplace can start imposing censorship," Obama said at a year-end news conference, speaking of executives at Sony Pictures Entertainment.

Sony said it had had no choice but to cancel distribution of the movie since theaters were refusing to show it.

Wire services