Attribution of the day

MEXICO CITY -- A trumpet player was found dead with his hands and feet bound and a plastic bag over his head in southern Mexico, in what authorities said was apparently the country's third slaying of a musician in less than a week.

Since we seem to know that he's a trumpet player, and that he was bound and (per the second graf) beaten on the head, what is it that we (and the authorities) are so unsure about?