From: Facebook <firstname.lastname@example.org>
Sent: Tuesday, April 30, 2013 1:25 AM
Subject: Did you log into Facebook from somewhere new?
Your Facebook account was recently logged into from a computer, mobile device or other location you've never used before. For your protection, we've temporarily locked your account until you can review this activity and make sure no one is using your account without your permission.
Did you log into Facebook from a new device or an unusual location?
- If this was not you, please log into Facebook from your computer and follow the instructions provided to help you control your account information.
- If this was you, there's no need to worry. Simply log into Facebook again to get back into your account.
For more information, visit our Help Center here:
Facebook Security Team
One way to know it is not a phishing email is to open a new browser window, log in to your facebook account (not from any links in the email!) and the alert should pop up again. Whether the alert pops up again or not, it would be my recommendation to go in there and change your password. And don't pick something stupid simple like "password123" or english words easy for a software to guess by running through combinations.