Another rogue app is replicating across Facebook by enticing folks to click on a video supposedly showing Justin Bieber being arrested for killing a 7-year-old boy while driving drunk.
No such video exists. No such arrest took place. Users who click on the blurbs are asked to okay the download of an app that will access their personal profile, friend list, and email address. Needless to say, this is a bad idea.
Always think twice before clicking on lurid posts promising "shocking videos" of this or that (most often a "dead" celebrity, "amazing" discovery, or other newsworthy event that hasn't really happened). Never grant an application access to your friend list, profile, or other account info unless you intentionally downloaded the app and have good reason to believe you can trust it.
This may be helpful: Facebook Security Tips
If you've inadvertently downloaded an app you don't want, instructions for removal are here.