A set of fingerprints led investigating officers to the perpetrator of a shocking crime in which a mother was stabbed to death while breast-feeding her four-month-old baby.

Thomas Manganyi, 30, was this month sentenced to life imprisonment for the gruesome murder of French immigrant Charlotte Coutron in December 2008.

He was given an additional 18 years for house robbery.

Police spokesman Captain Cynthia Magoai said Manganyi entered Coutron's home "somehow" in Parkhurst, northern Johannesburg, on December 8.

"She was at home with her baby when the accused came in and assaulted her with a sharp object," she said.

Manganye beat and stabbed the 30-year-old mother to death as her baby lay helpless besides her.

Coutron's husband, Maxime, was at work at the time of the murder and had apparently been trying to get hold of her all day, to no avail.

When he got home, he noticed that the security gates were open and became suspicious.

He reportedly contacted the neighbourhood security company. He and the company's guards discovered Coutron's bloodied body and the baby lying and crying next to her.

Police said Manganye had ransacked the house, taking with him a laptop computer, wallets, cellphones and clothing - including a pair of hiking boots.

Coutron had been in South Africa for only 15 months when she was killed. Her body was flown back to France for cremation a week after her death.

Her husband and the baby also moved back to France permanently.

Manganyie was arrested more than a week later at his home in Alexandra, northern Johannesburg, where most of the stolen goods were recovered.

"Fingerprints taken at the scene led police to the home of the accused and he was denied bail on his court appearance," said Magoai.

Manganye has been in custody since his arrest in December 2008.