Sort of like "Escape from New York" crossed with "Banlieue 13" but not quite?

It's a film i watched probably around 15 years ago and it didn't look new at that time. There's this area that looks like a scrap yard cut off by a fence and all the undesirables of society are being put into there. The big gang leader in there gets hold of some sort of biological virus in a missile (i think) and wants to kill all those outside the area. The government sends a sort of Snake Pliskin guy in to get it back. He meets a woman in there who tags along. There's a scene where she's captured by some religious cannibals and another where the guy has to fight some other dude while she's tied to a chair. Think the film ends with a gladiatorial fight on buggies. That's all the scenes i can remember. Been going mental trying to find this films' name.