Until this point all enemies where not hard to beat, but the big guys near the radio tower annoyed me. In the end I was able to kill him by emptying my machine and handgun on him a few times. Every now and then he seems to drop his shield when being fired at. Also I noticed that when you try to climb the wall to the burning roof, a Molotov cocktail is thrown to you. I was unable to time this so it would also hurt the shielded guy.
So, my question: what's the best strategy here?