I never had problems till I reach El Alma, but now my most poweful weapons (an M16 and a rifle) do 6 to 11 damage... 20 or 30 if I'm lucky. The enemies on the other hand can easily kill my men with two shots (they never miss, by the way). Somebody knows what's happening?
I've read that enemies become stronger as days pass, but I'm only on the fourth day!