There's also other bodies of USS agents dressed like Hunk, but they don't have masks. One is on the alley you unlock with the bolt cutter, across Moon Donuts (there's a explosive barrel and a few zombies. On the body you find a grenade and I think there's a suitcase with shotgun shells.). The other is after you cross the garage, just before you fight the dogs for the first time. There's a body of a USS agent and a suicide note next to it.
This might imply that other USS units were dispatched on Raccoon City to get rid of evidence for Umbrella (like in Operation Raccoon City, perhaps?) or...........it could just be Capcom reusing assets without much of a thought.