Updated info at Deadline.com, Warner Bros. has decided to pull the Gangster Squad trailer that was airing before The Dark Knight Rises in theaters. 

There is a scene in the trailer (2:04 mark below) where a few men pop out from behind a movie screen and shoot up a theater. Yeah. Probably a good call for Warner Bros. to pull that trailer for the time being.

(Sorry, they pulled the trailer already...for obvious reasons)