SAN FRANCISCO (TIP): Twitter said Friday thathackers, in the latest online attack, may have gainedaccess to information on a quarter of a million of itsmore than 200 million active users.The social media giant said in a blog posting thatearlier this week it detected attempts to gain access toits user data. It shut down one attack moments after itwas detected.But it discovered that the attackers may have gainedaccess to usernames, email addresses and encryptedpasswords belonging to 250,000 users.

Twitter has resetthe pilfered passwords and sent emails advising usersthat they’ll have to create a new one.”This attack was not the work of amateurs, and we donot believe it was an isolated incident. The attackerswere extremely sophisticated, and we believe othercompanies and organizations have also been recentlysimilarly attacked,” the blog said.

“For that reason wefelt that it was important to publicize this attack whilewe still gather information, and we are helpinggovernment and federal law enforcement in their effortto find and prosecute these attackers to make theInternet safer for all users.”The hack is the latest highprofilecyber-attack on US media and technologycompanies recently. The New York Times and The WallStreet Journal reported this week that their computersystems had been infiltrated by China-based hackers.One expert said that the Twitter hack probablyhappened after an employee’s home or work computerwas compromised through a vulnerability in Java, acommonly-used computing language whose weaknesseshave been well publicized.