North Korea swears it had nothing to do with the hack of Sony no matter what President Obama or the FBI thinks, and it has now called for a joint investigation with the US, reports Reuters. But it did so in typical North Korean fashion: "Without resorting to such tortures as were used by the US CIA, we have means to prove that this incident has nothing to do with us," says a government spokesman. He called American allegations "groundless slander" and warned that the US better cooperate in the investigation or risk "grave consequences."
But as the BBC reports, defectors say North Korea's military has a cyber-unit called Bureau 121 that has been known to use tactics similar to those used in the Sony hack. Last year, for instance, hackers calling themselves the Dark Seoul Gang infiltrated the computer networks of banks and TV stations in South Korea in generally the same fashion. The South thinks the gang is, in fact, the military's cyber-unit, reports CNN. (Meanwhile, Sony isn't happy with Obama's remarks, either.)