What was that scary movie not to long ago? please help this is driving me insane!

what was that scary movie that came out 2007 or 2008
with the girl with the shot straight brown hair
she can take her eye out and use it
shes some sort of opperative
and she goes into the quarantined zone
with some huge walls and when they go in
they're a bunch of cows and stuff
they go in because the gov't thinks they see movement
inside the quarantined area, which is like a huge thing
and finds bunches of people living there
some of them eat other people
some of them resorted to mideval times
and there is some tunnel
at the end she steals the jaguarWww@Enter-QA@Com

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