BOSTON (AP) — A suspect was arrested Monday in the weekend killings of a Boston-area husband and wife celebrating their 50th wedding anniversary and the woman’s 97-year-old mother, authorities said.

Middlesex District Attorney Marian Ryan said police took Christopher Ferguson into custody and charged him with killing 73-year-old Gilda “Jill” D’Amore after an autopsy revealed her death was a homicide. Ferguson also was charged with two counts of assault and battery with a dangerous weapon causing serious bodily injury, and burglary.

Additional charges were expected in the death of 74-year-old Bruno D’Amore and his mother-in-law, Lucia Arpino, after those autopsies are completed. Ferguson was expected to appear in court Tuesday or Wednesday. It wasn’t immediately clear if he had an attorney who could comment on his behalf.

The victims and suspect all live in the Boston suburb of Newton but Ryan said it appeared there was no connection between them.

The bodies were found in the victims’ home after the D’Amores failed to arrive at church Sunday morning, police said. Investigators found signs of forced entry into the basement and Ryan described a chaotic scene in which there were “obvious signs of struggle.” A crystal paper weight was covered in blood and furniture was broken.

The big break in the case came when authorities were able to match a bloody footprint to that of Ferguson, who lived in the neighbourhood, she said. They also collected blood stains near the footprints and bloody fingerprints on the screens and windows from the house, Ryan said.

The killings rattled Newton and the Our Lady Help of Christians Church, where the victims worshipped. A message to parishioners said the three “lost their lives in a senseless act of violence.”

The preliminary investigation indicated the victims died from stab wounds and blunt force trauma, Ryan said.