If I recall recorrectly, and we're talking about the guy with the LMG on the ship deck, I ran around avoiding his fire until a guy with an M32 Hammer appeared on the sidelines. I shot him, got the M32 and blew up the LMG guy. Maybe that was too hard, but it was fun. I thought it was the way I was "supposed" to do it.
Here's what I did on future runs: drop two grenades at him(if you have them), blindfire will kill him quickly, then pick up his machine gun and make mincemeat out of everyone else.

First time I beat the area your way though, and gave me a heck of a lot more trouble.