The man was seen using spray paint to leave a message on the side of his van.
Then he tied one end of a rope to a fire hydrant, the other end to his neck, and hit the gas leading to his decapitation.
CBS DFW reports the man’s head was thrown from the van, landing in the street.
Police say the van rolled to a stop without hitting anything or causing further damage.
The message on the van is in Spanish and reads “no codigo codbo,” loosely translated as “no code.”
Cops wouldn’t say much more but did confirm there were witnesses to the gruesome scene in west Dallas.
The man’s name has not been released.