Twitter has revealed that a hacker attack on their organization late on Friday may have caused 250,000 accounts to have been compromised, with passwords and other information believed to have possibly been accessed. The microblog website claims a precautionary has been implemented, which involved changing the passwords - which are encrypted - and are in the process of notifying affected account holders. "This attack was not the work of amateurs, and we do not believe it was an isolated incident." Twitter representatives declared earlier. "The attacks were extremely sophisticated, and we believe other companies and organizations have also been recently similarly attacked." Large scale cyber attacks have also been reported against other news organisations such as the New York Times and the Wall Street Journal; who unlike Twitter, gave details regarding the attacks, which are believed to have been launched by Chinese hackers. Jim Prosser, a Twitter spokesperson declared that the origin could not be speculated as their investigation was still ongoing. He also declared: "There is no evidence right now that would indicate that passwords were compromised." In 2010, Twitter signed a consent decree with the Federal Trade Commission, subjecting the company to 10 years of independent privacy reviews, for failing to safeguard users' personal information, as they had then suffered a breach - leading to questions over the efficiency of their system security.