Robert Gagnon to serve at least 40 years on charges that include Lyndeborough murder

Robert Gagnon, who murdered 83-year-old Robert Prest of Lyndeborough and shot 46-year-old Carlos Quintong of Brookline in November 2002, was sentenced Monday to a minimum of 40 years in prison.

Attorney General John Formella’s office announced that Gagnon, 47, was sentenced to 30 years to life on a second-degree murder conviction for killing Prest and 15 to 40 years for attempted murder for shooting Quintong. The minimum on the attempted murder conviction can be reduced by five years if Gagnon completes anger management counseling and is not charged with another crime.

Gagnon was also sentenced to 3 1/2 to seven years in prison on each of three Class A felony charges of theft by unauthorized taking, which are suspended for 10 years after his release on the murder and attempted murder sentences. They were related to Gagnon taking a Jeep SUV, a firearm owned by Prest and Prest’s BMW sedan as he tried to flee the scenes of the shooting and the murder.

The murder and attempted murder sentences are consecutive, making the total minimum sentence 45 years, or 40 if the minimum on the attempted murder charge is reduced.

Previous published reports and statements from Formella’s office say that on Nov. 23, 2002, the day before Thanksgiving, Gagnon shot Quintong multiple times through the passenger window at approximately 6:30 a.m. on Route 13 near Townsend Hill Road in Brookline. At approximately 9:21 a.m. the same morning, officers responded to a home on Center Road in Lyndeborough, where they found Prest dead. According to Formella’s office, an autopsy determined that Prest did from a homicide caused by blunt-impact head injuries from being struck by a hatchet.

Police searched in Lyndeborough, Brookline, Greenfield, Milford, Wilton and Nashua for the suspect before police found Gagnon in Nashua at around 12:15 p.m.