Similar thing happened to me the other day feeding my BP his first adult/large mouse. Soon as he struck and constricted. I noticed my BP had the mouse by it's jaw, and the teeth from the top, was close to biting down on my BP's mouth. So I immediately stuck the metal tongs in the mouse's mouth and could feel the upper teeth biting down on the tong. I definitely prevented the mouse from chewing into my BP's mouth. After the mouse was officially dead, I tuck out the tongs to clean it. And I noticed a speck of blood on the tong, not sure if it was from the mouse or my BP. Pretty sure it was from the mouse, I hope so. Lol