By Brendan Sasso - 02/02/13 01:16 AM EST
Twitter revealed on Friday that "extremely sophisticated" hackers attacked its site this week, potentially gaining access to information on thousands of users.
"This attack was not the work of amateurs, and we do not believe it was an isolated incident," Bob Lord, Twitter's director of information security, wrote in a blog post.
He said the attackers may have gained access to "limited" user information—including usernames, email addresses and encrypted passwords—for about 250,000 users.
Lord did not name any suspects in the attack, but he noted that The New York Times and The Wall Street Journal experienced similar attacks this week.
Those newspapers said they believe that Chinese hackers had tried to access their computer networks to monitor their coverage of the country.
"The attackers were extremely sophisticated, and we believe other companies and organizations have also been recently similarly attacked. For that reason we felt that it was important to publicize this attack while we still gather information, and we are helping government and federal law enforcement in their effort to find and prosecute these attackers to make the Internet safer for all users," Lord wrote.
He recommended that users rely on a strong password and disable Java in their browsers, citing an advisory from the Homeland Security Department.