I think this man has been killd by burglars because he was rich.
I think there was Two persons because we see Two cups of wine. There are luxury objects Like a trophy and safe. We can see that the door is opened and all pièce of furniture are overturned.
The suspicious go arrest because he has let the évidence like imprits on the weapons of the crime. The victim is maybe guilty. There aren't any witness. Maybe that other person has been kidnapped because there are Two cups and it´s very fishy. Thé police investigates into this affair to find the culprit