A number of Facebook users have reported to us receiving mysterious messages telling them that their accounts have been suspended. The spam messages, however, are not legitimate. In reality they have been sent out by fraudsters posing as Facebooks real security team, with the intention of phishing credentials from unsuspecting users. The messages are not genuine, but they are meant to be phished credentials by phishing the credentials of unsuspecting users, such as Facebook users who have not responded to the messages.”]
Source: https://grahamcluley.com/fake-facebook-security-team-phishes-passwords-from-users/