According to police, the 32-year-old man and his 29-year-old wife started arguing while driving from Essen to Dortmund. The situation escalated dramatically when the man, who was at the wheel, pulled out a knife and stabbed his wife in the throat.
At the same time, he lost control of the vehicle and collided with a crash barrier. At this point the seriously injured woman was able to escape from the car and run away.
The man attempted to drive on, but only made it a few more metres before coming to a halt in the middle of the road. He then got out of the car and climbed over onto the other side of the motorway, where he ran into the oncoming traffic.
A car coming from Wiesbaden struck and killed him. According to police, the man's actions were a suicide attempt.
Both driver and passenger in the oncoming car were badly injured and needed to be taken to hospital by helicopter. A third car also crashed after the driver swerved to avoid hitting the man's body as it lay on the roadway.
An 30-man emergency service team was involved in the subsequent rescue operation.
The man's 29-year-old wife was taken to hospital but the wounds to her neck were not considered life threatening.
The police in Bochum have now opened a murder investigation.