Security seems very tight on The Dark Knight Rises set. Very tight. The Hollywood Reporter says:
Batman (Christian Bale) fights villain Bane (Tom Hardy) in new footage WPIX captured from The Dark Knight Rises’ Pittsburgh set over the weekend. As The Huffington Post points out, the clip shows a brawl between the Gotham City Police and the Arkham Asylum inmates. Snow swirls all around as cops beat down inmates and Batman pushes Bane up the stairs. Local resident and extra Erin Giambelluca tells the Forest Hills-Regent Square Patch site that it was hot outside and extras drank tons of water to stay cool in their winter-weather costumes. “Right after the football scene ended, they did one explosion,” she says. “It looked like pieces of grass all over the field to make it look like it was blown up while the players were on it, and we had to wear ear plugs for that. We had to rehearse and make sure we weren’t smiling during that part.”
Please keep in mind that this video hit online three days after Warner Bros. was forced to post an image of Anne Hathaway as Catwoman because pics taken by people just hanging out around the set were about to hit online. So in closing, if you want to shoot a movie that people can see two years before it comes out, Pittsburgh seems like a pretty good place to do that.