A thief stole banking information of 29,000 current and former Facebook employees last month, Bloomberg first reported.

The data was reportedly stored on unencrypted corporate hard drives, which the thief stole from a Facebook employee's car.

Facebook reportedly alerted employees of the breach in an email to staff Friday morning.

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A thief reportedly broke into a Facebook worker's car last month and stole several corporate hard drives containing the banking information of 29,000 current and former Facebook employees, first reported by Bloomberg.

The stolen data reportedly included employee names, bank account numbers, and last four digits of social security numbers. Information about salaries and bonus amounts was also included on the drives. "This theft impacts current and former Facebook employees only and no Facebook user data was involved," a company spokesperson told Business Insider.

Facebook alerted employees to the stolen data in an email Friday morning.

In a statement, Facebook said it was working with law enforcement, and that it believes "this was a smash and grab crime rather than an attempt to steal employee information."

According to Bloomberg, the employee whose car was broken into worked in Facebook's payroll department and broke protocol by taking the hard drives outside the office.

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