Christopher Piantedosi, 39, of Methuen, Mass., was arrested Friday and charged with one count of murder after turning himself in to Massachusetts State Police, The New Hampshire Union Leader reported.
"Based upon the physical evidence and based upon the observations of the investigators at the scene, this killing was the result of a very angry rage," Middlesex County District Attorney Gerry Leone said.
Piantedosi, who is scheduled to be arraigned Monday, is the same man who returned a wallet, money and GPS to a New Hampshire woman he stole the items from in July and was later dubbed the "remorseful robber" by Plaistow police.
He pleaded guilty to theft charges and was given a 30-day suspended sentence.
The stabbing of Piantedosi's girlfriend, identified as Kristen Pulisciano, 38, was reported to Burlington police Thursday evening by a 15-year-old girl. When officers arrived, Pulisciano was found with multiple stab wounds and was pronounced dead at the scene, authorities said.
"We can't now know exactly what triggered this heinous act of murder. We do know that there were some issues and some problems and some indicators of violent acts, exercise of power and control by this defendant against this victim leading up to the murder," Leone said.