I got this pic from Facebook which reveals the truth about what exactly is happening on the famous social networking site. There is kind of virus which has been spread by some Hackers.
What actually you have to do if someone posted this; 1. Don’t touch it else it will be shared with your friends. 2. Ask for the Facebook help 3. See the screenshot below to know where to click for help (it’s on the right side bit below) and follow the steps further carefully.