The head of former Brazilian footballer Joao Rodrigo Silva Santo was left outside his wife house in Rio de Janeiro (G1 Globo)

Suspected drug traffickers killed a former Brazilian footballer and delivered his severed head to his wife - a policewoman - in Rio de Janeiro.

Joao Rodrigo Silva Santo, 35, was kidnapped at night as he left the food shop he was running in the district of Realengo since retiring from football.

Early in the morning, his wife, an officer with Rio's police Pacification Units (UPPS), reportedly heard a noise coming from outside her house and went out to check.

A backpack she recognised as Santo's was on the floor outside of the door. Inside was her Santo's head.

G1 Globo website reported the assailants had carved out the man's eyes and the tongue.

"He was a good family man. He lived for football and played until recently," Bruno Santos, a friend of the victim told the news outlet. "He had no enemies."

Santo played in several Brazilian teams, mainly in lower leagues and also briefly in Sweden.

Police said they suspect local drug traffickers for the gruesome murder.

UPPS, Santo's wife police unit, have been involved in a crackdown on Rio's gangs launched by the government to clean up Brazil's main cities from crime ahead of the 2014 World Cup and 2016 Olympics.

Under the so called "pacification" programme police, often backed by helicopters and armoured vehicles, have raided dozens of favelas and shanty town, especially in Rio's outskirts to chase away crime gangs.

Former footballer Joao Rodrigo Silva Santos was killed in Rio de Janeiro (Courtesy of TV Globo)