After a lawsuit, Instagram co-founder resign and shares drop, Facebook is hit with another blow.

Guy Rosen, Facebook’s VP of product management, rest access to affected accounts and logged out 90 million accounts as a secrity precautin after a hack of nearly 50 million accounts.

NY Post reports that the breach was discovered on Tuesday by Facebook and it allowed them to take over accounts. Rosen said it’s unclear if accounts were misused but there is an investigation.

“People’s privacy and security is incredibly important, and we’re sorry this happened,” said Rosen.