Like as @Pooya87 already stated "considering the source is US justice department", it is more likely to be a rumour
Perhaps Pooya87 isn't saying that what ever that is from the US justice department is a lie or isn't true but considering the fact that US government likes to pin crimes on government which they do not like and pretend to be clear that is the most important point.
The US might do worst yet wouldn't get to our hearing, NK might be aware of the criminal hack gang yet with it's anonymous and might not be able to do anything about it, but if true they are sponsors to this group then NK more but the smartest country ever LOL