Robert McKenna, 43, was found dead in a pool of blood inside his home on Sept. 16

By Tara Fowler
Updated September 29, 2015 01:15 PM

A Dorchester, Massachusetts, man who has 46 prior convictions for violent crimes has been charged with murdering a man who had claimed to have a large diamond in his home, PEOPLE confirms.

James Ferguson, 39, is charged with stabbing to death Robert McKenna, 43, in McKenna’s Marshfield home earlier this month. Prosecutors said Monday that McKenna had previously bragged to friends about the diamond from his days as a diamond runner in Africa. That diamond was missing from the home after he was found dead.

Ferguson was taken into custody over the weekend after DNA evidence left at the scene matched his profile in CODIS (Combined DNA Index System), the Plymouth County District Attorney’s Office said Sunday.

“It’s disturbing that people go in and out of our system, can commit violent crimes and can sell drugs. He was basically doing life on the installment plan,” Plymouth County District Attorney Timothy Cruz told reporters on Monday.

McKenna was found dead by a friend in a pool of blood inside his home on Sept. 16. He had deep cuts from a knife to his right arm, hands and the back of his head. The cause of death was determined to be blood loss.

Ferguson denied having anything to do with McKenna’s death and has pleaded not guilty to the charges against him.

Police are still looking for two other suspects in the crime, a man and a woman.

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