I am a homicide detective on the magical police force. Runes are magical symbols fused into objects that imbue those items with magical power. These spells are stored in these runes for long term use to provide immediate access. Runes generate large amounts of heat when they are activated, which is why they are are usually placed on items and not on the skin. However, a horrific use has been found that evil mages use to there advantage.
Evil mages have been using innocent people as human bombers to hit specific targets, do damage to approaching armies, or simply to send a message. A special rune is magically fused to the skin which the witch is mentally attached to. The witch can then control the individuals movements, leaving them aware with the mages controlling them from a distance. At the mages will, the rune activates, turning the person into a human bomb. The explosion vaporizes the area closest to them, and anyone caught in the blast is blown to pieces.
There is however something strange about how the rune operates. When normal suicide bombers activate their explosion, their own body also suffers damage and is blown apart, leaving little to clean up by the authorities. In this case, the body is burned to a crisp, but remains intact. The charred corpse remains in one piece, with everything else either vaporized or destroyed.
When a bomb explodes,the force of the explosion travels outward, destroying everything in the vicinity with the victim at the center of it suffering the most damage. This rune works differently, destroying the surroundings while leaving the body itself intact, albeit burnt to a crisp. I need to explain how the force of this bomb would propagate away from the victim without damaging the remains themselves.