Snakebite as a surreptitious form of murder has been featured in stories such as Sir Arthur Conan Doyle's "The Adventure of the Speckled Band", but actual occurrences are virtually unheard of, with only a few documented cases. It has been suggested that Boris III of Bulgaria, who was allied to Nazi Germany during World War II, may have been killed with snake venom, although there is no definitive evidence. At least one attempted suicide by snakebite has been documented in medical literature involving a puff adder bite to the hand.