The United States has imposed new sanctions on North Korea as part of its first response to the cyber attack on Sony Pictures.
The FBI has blamed North Korea for the attack which leaked confidential data from Sony computers.
North Korea has denied the allegation but expressed fury over Sony's comedy The Interview, which features a plot to assassinate leader Kim Jong Un.
Experts have warned that online access is "totally down" in North Korea as the nation experiences serious internet problems.
It is not immediately clear if the internet connectivity problems were an act of retribution for a major intrusion at Sony Pictures Entertainment which the FBI last week linked to North Korea.
The White House declined to comment on the problems but State Department spokeswoman Marie Harf told reporters that of the federal government responses, "some will be seen, some may not be seen".
North Korea's dispute with the US over computer hacking took a new twist when the communist state lost Internet access for several hours.
A hacker group who claimed to be behind a cyber attack on Sony Pictures have posted a message online apparently mocking the FBI.
Events company Secret Cinema is planning to screen a film in protest at what they have called the 'censorship' of The Interview.