A German decapitated his lover with a machete, sped off with the severed head and drove straight into a truck, killing himself.
"We found her head in a rucksack on the front seat of his car," Werner Kramer, senior state prosecutor in the northwestern town of Leer, said on Thursday. "There's no question he drove right into the truck on purpose."
Investigators believe the pair had had an argument before the killing on Wednesday.
The 32-year-old mechanic left the woman's body in his bedroom and fled after setting his flat on fire with petrol.
Police found the machete in the bathroom of the burnt-out flat.