It comes days after President Obama pledged a "proportional response" to the communist country's alleged hacking of Sony Pictures. It's unclear what caused the outage.
North Korea's National Defense Commission, which is headed by the country's leader, Kim Jong Un, said its military was ready to fight America "in all war spaces including cyber warfare space."
The protest at the Letpadaung project comes two years after police forcefully dispersed demonstrators at the site. Villagers had complained of health and environmental problems related to the project.
The Obama administration has asked China to help rein in North Korea's cyber capabilities. The administration wants China to help block further attacks, like the massive hacking of Sony Pictures.
On CNN's State of the Union, the president expanded on earlier remarks he made criticizing a decision by Sony Pictures to pull distribution of The Interview.
The FBI says North Korea was responsible for the Sony cyber hack. North Korea denies involvement. NPR's Rachel Martin talks about possible next steps with Georgetown University professor Victor Cha.
The controversy around The Interview is a top story in the U.S., but those in North Korea have no knowledge of the film. NPR's Arun Rath talks with Washington Post Tokyo bureau chief Anna Fifield.
The inmates were sent home on a request from the new Afghan president, Ashraf Ghani. It is the latest in a series of moves to draw down the prison population by sending prisoners abroad.
The FBI has concluded North Korea was responsible for the cyber attack on Sony Pictures. NPR's Scott Simon talks with White House correspondent Scott Horsley about what happens now.