Jill and Bruno D'Amore, and Lucia Arpino were beaten and stabbed to death Sunday morning inside a Broadway Street home, the family wrote in a letter to Our Lady Help of Christians, the trio's church.
The D'Amores leave behind three children and five grandchildren, the note said.
Police said there were signs of a break-in at the home. There was an attempted home invasion about half a mile away from the D'Amores' home Sunday morning, but police have not said if they are connected.
A friend found the bodies when the trio failed to show up for Sunday morning mass at Our Lady of Help of Christians, and they went to check on the family.
The church will hold a "Mass for Peace" for the victims on Tuesday from 6:30 to 7:30 p.m. at 573 Washington St. in Newton.
Police have increased patrols in the area.
Authorities ask anyone in that area to remain vigilant, lock their doors and windows, and immediately report anything suspicious to Newton Police at 617-796-2123 or 911 if it appears to be an emergency.
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