A former Brazilian footballer, João Rodrigo Silva Santos, has been decapitated and his severed head delivered to his policewoman wife. Police in Rio de Janeiro said they suspect local drug traffickers.

The police unit that Santos's wife belongs to has been involved in a crackdown on Rio's gangs launched by the government to clean up Brazil's main cities before the 2014 World Cup and 2016 Olympics.

Santos, 35, was kidnapped at night as he left the food shop he was running in the district of Realengo after retiring from football.

Early in the morning, his wife heard a noise outside her house and went out to check.

A backpack she recognised as Santos's was on the floor outside of the door. Inside was Santos's head. The G1.globo website reported the assailants had carved out the man's eyes and tongue.

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

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

He began with Bangu in 1996, before having stints at Olimpia, Nacional and the Swedish club Östers.