Social media giant Twitter says it was hacked recently, in a sophisticated cyber attack that exposed the passwords and other information of about 250,000 users.

The company said in a blog post that it had detected unauthorized attempts to gain access to its user data. The site's information security director, Bob Lord, said Twitter employees discovered one live attack and shut it down in process moments later.

Twitter said it reset passwords and that it was notifying affected users.

Unlike the New York Times and Wall Street Journal newspapers, which said they were attacked by Chinese hackers, Twitter did not provide any information on where the hacking had originated. But Lord said in the posting that the attack was "not the work of amateurs," and that Twitter does not believe it was an isolated incident. He called the attackers "extremely sophisticated."

The company said it is working with government and federal law enforcement in their effort to track down the attackers to make the Internet safer for all users.

VOA News, "Twitter Hit by Cyber Attack"