A pair of pitbulls started to eat the body of their trainer after he died in his apartment in Madrid, authorities have said.
The victim was identified as Angel Javier, 34, who advertised his services online as a trainer of dangerous dogs.
Police believe the dogs did not begin to eat the victim until he was already dead. The coroner told reporters he died of a heart attack. Investigators found no evidence of foul play.
The authorities would not speculate on whether or the pitbulls had played a part in his death.
His body was found by his girlfriend, who visited his flat in the district of El Molar because he had been missing for two days.
The woman, who has not been identified, was hit by an overpowering stench when she opened the front door. She saw the two dogs and faeces all over the floor.
Her boyfriend's body was on the bed. Parts of his head had been ripped off by the dogs.
El Mundo said Javier's face "was shattered by bites" and lacerations were found all over his body. Fingerprint analysis had to be used to confirm his identity.
Reports claimed that the dogs had begun to eat Javier because they had no food or water.
Pitbulls are classified as dangerous dogs in Spain and have to be muzzled outside the owner's home. Prospective owners of such dogs have to undergo a psychological test before they are allowed to buy one.
Attacks still occur, however, the most recent in early June when a rabid pitbull attacked four children and a teenager in Castile-La Mancha. It was the first recorded case of rabies within the Iberian Peninsula for almost 40 years.
Local authorities declared a state of high alert and all dogs and cats within an 18-mile radius were given a compulsory vaccination.