Sony Pictures Entertainment starts investigating the system hacking that happened on Nov. 24, Monday.
For more than a week, the film studio went down after a widespread hack that affected all computer systems. On the 24th, employees couldn't log in on their computers. When they try to get into their account, a message appeared on the screen, saying "Hacked By #GOP."
GOP, said to mean Guardians of Peace, threatened the company to meet their demands, or they'll publicly release the secrets they've obtained from the company.
An insider said that the Federal Bureau of Investigation is already looking into the matter. The company also hired Mandiant, a forensics unit of the security firm, FireEye.
Sony said in a statement, "The company has restored a number of important services to ensure ongoing business continuity and is working closely with law enforcement officials to investigate the matter."
The film studio is back to business on Monday, Dec. 1, and the systems were expected to go back up and to run as smoothly as ever.
A day after the hacking, unreleased Sony movies were leaked online. DVD copies of the movies appeared on streaming and torrent sites, including Brad Pitt's "Fury," the remake of the musical "Annie," true-to-live "To Write Love On Her Arms," and Julianne Moore's "Still Alice."
"The theft of Sony Pictures Entertainment content is a criminal matter, and we are working closely with law enforcement to address it," said Sony.
FBI confirmed that they're working with Sony to crackdown the culprit of the hacking.
"The targeting of public and private sector computer networks remains a significant threat, and the FBI will continue to identify, pursue, and defeat individuals and groups who pose a threat in cyberspace," said Laura Eimillier, an FBI spokeswoman.
There were initial reports that North Korea was behind the hacking, but cybersecurity experts dispelled the rumors.
