The player's eyes and tongue had been cut out and his head placed inside one of his own rucksacks, police said. Mr Santos retired from football two years ago after a successful career playing for several teams in Rio de Janeiro, as well as for clubs in Sweden and Honduras.
He had recently set up his own business selling health foods and dietary supplements.
Police said today that Mr Santos is believed to have been snatched from outside the shop he had opened in the Realengo district of Rio as he closed up at around 7.45pm on Monday.
Witnesses said they saw several men bundling him into his car, a Hyundai i30, and speeding off just before midnight, a spokesman said. He was reported missing by his wife at 9pm on Monday.
Mr Santos' brother-in-law, who didn't want to be named, told Brazil's Globo G1 website that the player's wife, Geisa Silva, 31, stayed up all night after her husband failed to arrive home.
He said: 'Every time a car passed by she would go to see.
'She was getting ready to go to work at around 5.30am when she heard a noise, opened the front door and saw his rucksack.
'When she opened it she discovered it contained his head.
'I did not want to look but the people who saw it said they had gouged out his eyes and cut off his tongue,' said the horrified relative.
Neighbours living close to the crime scene reported hearing a woman screaming: 'My God, it's Joao! It’s Joao’s head.'
From what I know, he didn't have any enemies and neither did his wife,' the relative added.In a statement Mr Santos' widow said the couple had not been subjected to any threats.
Lead murder investigator Rafael Rangel from the 14th Military Police Battalion (BPM) in Rio, said witnesses saw armed men kidnap the businessman. 'We believe that the people who took him knew the family’s routine,' said Rangel.
Investigators are working on the hypothesis that Mr Santos could have been murdered by a drugs gang because of Mrs Silva's work at a military police base in a local slum.
The Police Pacification Unit in the Morro do Sao Carlos is one of dozens set up in Rio's favelas to retake control of the city's slums from violent drug traffickers.
However, according to police chief Rafael Rangel, Mrs Silva worked as a social worker in the base and didn't patrol the streets or make arrests like other police officers.
He told Brazil's O Dia newspaper the motives of the murder are still unclear.
He said: 'Mrs Silva has no idea who would have done this. Neither she, her husband or any other member of the family have suffered any type of threat as far as she knows.
'There is nothing that would justify such a barbarous crime.'
Santos did not have a police record.
Later today Brazilian police said body parts dumped beside a city river were believed to be those of Mr Santos.
The player's brother-in-law told Brazil's Globo G1 website that family members had positively identified a torso found next to the Guandu river in Queimados, greater Rio de Janeiro, by a birth mark on Mr Santos' stomach.
A police spokesman said other body parts had also been found in the area and were being DNA tested.
He said the murder bears the hallmarks of an execution by drug gangsters, but stressed that "every line of investigation" is still open.
The couple had been together for 11 years and were described as ‘lovely’ by neighbours.
'They were a happy, quiet couple,' said a neighbour, who asked not to be identified. 'But you never know what may have motivated a crime as stupid and as senseless as this.'
Mr Santos’ played as a professional footballer between 1996 and 2005 - during which he scored 33 goals in 103 matches as a striker. Nicknamed Humble Hero, he was signed to a number of second division teams. He also played abroad for Swedish Club Oster Vaxjo and Olimpia in Honduras.
A recent United Nations report into drug trafficking-related crime in Brazil found that more than half of the homicides, robberies and thefts have a direct or indirect link with this criminal activity.
Culled from UK Daily Mail