Assuming this is an MP mission, very easy.
Also assuming you know how to make units respawn in MP, All you have to do is make a normal respawning description.ext, then just make a trigger, so
condition = !Alive Mr_Dude
Activation = Deletevehicle Mr_Dude
Then just set the number of times to redo to repeat and your good to go!
Also to make it look cooler you may want to make a loop to have the units sink into the ground before making them dissapear, or make another condition which checks if anyone is near the body, thus eliminating the annoying hassle of running to the body to grab his gun and watching him dissapear before you can get it.