The couple found killed on Tuesday in their Marshfield home were mourned Thursday at the Home Depot store in Plymouth where they had worked for the past four years.
“We are all in a state of shock,” said Lorraine Puleo, the store manager. “Just beloved employees. I have contractors coming in, I have former associates coming in, and the extended Home Depot family reaching out to me, just to share the profound loss that they felt.”
Carl W. Mattson, known at work as “Bud,” and his wife, Vicki L. Mattson, were 70. Law enforcement are searching for their alleged killer, Christopher M. Keeley, a 27-year-old who had been staying at their Gotham Hill Drive home but had been asked to leave, according to a State Police affidavit filed in court.
Keeley, who lived in Weymouth, allegedly told a friend last Friday that he had attacked the couple, who were found stabbed and bludgeoned to death.
“Keeley told him that when he was in his old room, in the house in Marshfield, there was an altercation with the older male resident because of the dog barking. Keeley then described an altercation that resulted in Keeley ‘killing them,’ ” State Police wrote in a summary of the friend’s account to investigators. “Keeley did not describe how he killed them, but stated that there is a 1 percent chance they are alive.”
The dog was found dead inside the home, the Plymouth district attorney’s office said Thursday. The dog’s death is part of the murder investigation.
The day after the alarming conversation, the friend asked the police to check on Keeley’s well-being, court records show. When officers knocked on the door, no one responded, and a Mattson family member later told police that Keeley had moved out and was living in Quincy, State Police said.
Police returned on Tuesday after Keeley’s friend provided more details about the alleged attack on the Mattsons, leading to the grisly discovery of the slain couple.
It is not clear when they were killed. They were last known to be alive on Thanksgiving, when they celebrated the holiday with relatives, according to court records.
Authorities said that Keeley stole a black Jeep Wagoneer from the Mattsons. The car was found Wednesday in a parking lot in Avon.
Keeley has a history of mental health issues, Plymouth District Attorney Timothy J. Cruz said at a news conference Wednesday, and a relative of the couple described him as “crazy” to investigators. A friend of Keeley’s told investigators he had seen him recently and that he was in a “psychotic” state.
Keeley, according to friends interviewed by State Police, was anxious about becoming homeless if the Mattsons ordered him to leave. On Thanksgiving, a woman had kicked him out of her home after he assaulted her, according to the affidavit. A friend dropped him off near the Mattsons’ home that night, State Police said.
Keeley pleaded guilty to participating in a 2014 beating and robbery of an autistic man in Weymouth, according to court records and State Police. The judge who oversaw the case ordered that Keeley undergo a mental health and substance abuse evaluation before sentencing him to a year behind bars, records show.
Keeley’s mother told investigators “he knows he is not allowed” at her home.
In a statement released by her lawyer, the Keeley family extended their condolences.
“The Mass State Police have been given the full cooperation of Mr. Keeley’s family. The events that are alleged to have occurred are shocking and truly devastating to all involved,” the family said in a statement. “Our hearts go out to the entire Mattson family for their unspeakable loss.”
Relatives of the Mattsons could not be reached on Thursday.
The couple had worked at several Home Depot locations for over 25 years, before settling in at the Plymouth store, said Pam Marlowe, a spokeswoman for the retailer.
“Bud and Vicki Mattson . . . were beloved by our Home Depot family and customers alike,” Marlowe said in a statement. “Our Plymouth associates had been looking forward to celebrating Vicki’s birthday with her this week, and everyone there is taking this news very hard. Our hearts are with their family and friends.”
Bud Mattson worked in the tool rentals and Vicki Matson was a regular in the paint section.
“They were in semi-retirement, working only a few days a week,’' she said. “They were just wonderful people. I have no other words, no other words to describe the loss we feel.”
Marlowe said she spent Thursday speaking with the Mattsons’ co-workers, who told her the couple were inseparable and always first in line to help when someone was in need.
“When there was a party, they were the life of the party,” she said. “When one of them was sick, the other would take the day off and stay home with them.”
Mike Bello of the Globe staff and correspondent Jeremy C. Fox contributed to this report.