Facebook Inc said on Friday it had confirmed that the attackers in the mass security breach it announced late last month accessed the accounts of about 30 million people in total and stole name and contact details for 29 million.

Facebook Inc said in late September that hackers stole digital login codes allowing them to take over nearly 50 million user accounts in its worst security breach ever, but did not confirm if information had actually been stolen.

The company said that for 15 million people, attackers accessed two sets of information – name and contact details including phone number, e-mail, or both, depending on what the individuals had on their profiles.

For another 14 million people, the attackers also accessed other details included username, gender, locale/language, relationship status, religion, hometown, current city, birthdate, devices used to access Facebook, education, work, and the last 10 places they checked into or were tagged in.

"We’re cooperating with the FBI, which is actively investigating and asked us not to discuss who may be behind this attack," Facebook said on a blog post.

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