BILLERICA, MASS. (WHDH) - Three men were sentenced to prison this week after pleading guilty in the death of a 22-year-old man who was found murdered in his Billerica home in 2012, prosecutors announced Friday.

Sophan Keo, 32, of Beverly, Steven Touch, 30, and Gabriel Arias, 27, both of Lynn, pleaded guilty in Middlesex Superior Court to charges including manslaughter, conspiracy to commit armed robbery, attempted armed robbery, home invasion, and conspiracy to commit home invasion, Middlesex District Attorney Marian Ryan and Billerica Police Chief Daniel Rosa said in a joint news release.

Judge Kenneth J. Fishman sentenced all three men to 10 years in state prison for their roles in the death of Quintin Koehler.

On July 7, 2012, investigators say a group of masked men smashed a door from its hinges at home on Boston Road around 3:50 a.m. They then shot and killed Koehler when a pair of residents tried to force them out of the home.

Massachusetts State Police and the Billerica Police Department later analyzed cellular phone records and DNA evidence recovered at the crime scene, linking six men to the murder, including Keo, Touch, and Arias. Investigators say the group had set out to steal cash and marijuana from the victims.

Arias carried a weapon into the home, while Touch and Keo provided transportation, according to investigators.

Adam Bradley, who organized the plot and recruited the participants, was sentenced to life without the possibility of parole in 2017. While awaiting trial, the 34-year-old Lynn native is said to have written letters from jail asking known gang associates and acquaintances to have the prosecution’s cooperating witness killed.

Jason Estabrook, 34, of Lynn, and Peter Bin, 30, of Peabody, were also previously sentenced to life without the possibility of parole for their roles in the incident.

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