U.S. Links North Korea to Sony Hack Attack

U.S. federal law enforcement agencies have concluded that North Korea was involved in the planning and execution of the devastating cyber attack against Sony Pictures Entertainment three weeks ago, a source familiar with the investigation has confirmed to Re/code.

NBC News late Wednesday reported that American intelligence officials believe the attack was launched from outside of North Korea, but was carried out on the country’s behalf. “We have found linkage to the North Korean government,” a U.S. government source told NBC.

The news of the government’s conclusions confirms what Re/code first reported on Nov. 28: That the attack was thought to be part of an effort to prevent the release of “The Interview,” a Sony Pictures film that depicts the assassination of North Korea’s leader, Kim Jong-un. Earlier today, Sony canceled theatrical screenings of the film after threats of violence from the same attackers who crippled its internal corporate network.

Spokespeople for the FBI, Department of Homeland Security, the Department of Justice and Sony have not yet responded to requests for comment.

The country had previously denied any connection to the attack, while praising it as a “righteous deed.”

Threats of violence against movie theaters within the United States changed the map on how government investigators could officially respond to the attack. What started as an expensive and embarrassing corporate security issue transformed into a matter of national security once the hackers known as the Guardians of Peace threatened terrorist action in U.S. theaters.

“The threat of violence would have triggered a lot of information-sharing between government agencies and agencies in other countries,” said Phil Lieberman, CEO of Lieberman Software, a firm that supplies security software to large companies, including the Hollywood studios, and to government agencies.

The attack was made public on Nov. 24 when Sony’s internal corporate network was crippled. Over the course of the next three weeks, the attacks escalated, with numerous disclosures of sensitive corporate information on both its business plans and the personal information of its employees. Five films were leaked to file-sharing networks, along with the email archives of several Sony Pictures senior executives.

The Guardians of Peace has promised the release of more documents and data. After a steady stream of daily document drops on Saturday, Sunday and Tuesday, the group was silent today.

This article originally appeared on Recode.net.