This is the case where the woman was killed by the two men in the field. What always confused me is why the witness "Antonio" stood there and watch it happen when he was armed with a gun? He could have saved her life. He was concerned enough to call the police after the fact but didn't do anything to stop it while he had a gun in his hand.

I don't recall him having a gun in the reenactment. It's possible that Unsolved Mysteries added that in for effects but Antonio probably never really had a gun. He was already illegally hunting in a sugar cane field, so he probably didn't want to lead on that he had a gun (If he did).

he had a rifle.

Most likely because he was the killer giving a phony description of the killers, or had heard the killer bragging about it & in reality wasn't there when it happened. The fact that he was armed means if he was telling the truth he is a pathetic excuse for a human being watching somebody get killed in front of his eyes when he could have prevented it-don;t know how anybody could live with themselves knowing they just let somebody be murdered when they had the means to prevent it.