An 18-year-old Massachusetts high school senior was ordered held without bail Friday after prosecutors said he broke into a Danvers home and fatally stabbed Janet Swallow, a 68-year-old intensive care nurse, as she slept in her bedroom.
The case has shaken the North Shore because prosecutors say there was no known connection between Anthony DeMayo of Lynn and Swallow, a longtime Danvers resident and nurse at Lahey Hospital & Medical Center in Burlington. Investigators say the attack appears to have been random, with no sign of robbery and no threat to the public after DeMayo’s arrest. The court case is now moving on two tracks at once: a murder prosecution and a psychiatric evaluation ordered after a court clinician raised concerns about DeMayo’s mental state.
Prosecutors laid out a timeline that began late Wednesday and stretched across several communities by Thursday afternoon. Court records say DeMayo drove through nearby towns before stopping in Danvers near a home under construction. Investigators say he then chose a nearby house, ripped a screen from a back window and climbed into the kitchen of Swallow’s home on Amherst Street. According to prosecutors, he moved through the house, found Swallow asleep in a bedroom and stabbed her in the neck. They said the knife became stuck and that she was pulled from the bed onto the floor before he left and drove back to Lynn. Cellphone data later cited in court placed his phone in a Danvers neighborhood from about midnight to 1 a.m. Thursday. By about 11:50 a.m. Thursday, Lynn resident Ashley O’Brien said she saw a young man carrying a kitchen knife, swinging it and “stabbing all these bushes” near her home, prompting the 911 call that brought police to him.
What first looked like a disturbing street encounter quickly became a homicide investigation. Authorities said Lynn officers found DeMayo on Standish Road acting erratically and carrying a knife with what appeared to be blood on it. Because of his condition, officers took him to Salem Hospital. Prosecutors said DeMayo then told police he had killed a woman in Danvers the night before. State police obtained a warrant to search his Lynn home and said they found bloodstained clothing and other evidence. That evidence, along with data from his phone, led officers to 17 Amherst St. in Danvers for a welfare check Thursday evening. Swallow was found dead inside. Prosecutors said there was no indication anything had been taken from the house and that investigators believe DeMayo acted alone. Essex County District Attorney Paul Tucker later said investigators had found no connection between DeMayo and Swallow, a detail that has made the killing harder for residents to absorb. Officials still have not publicly explained why Danvers was chosen that night or whether there were warning signs before the attack.
Swallow’s death has touched more than one community because of the life she led before the violence. Friends and co-workers described her as steady, kind and deeply tied to her family and her work. Lahey Hospital & Medical Center said she was “a beloved and valued member” of its nursing staff. Danvers police said she leaves behind two sons. On Friday, flowers and tributes began to gather outside her home, and friends stood with neighbors on the street where she had lived for years. Stephen Bardell, a family friend, said he had “fond memories” of Swallow and described her as someone who helped him through hard times when he was young. Diego Demelo, who knew her through nursing, said she had mentored new nurses and brought calm to the job. The attack also sent shock waves through Bishop Fenwick High School in Peabody, where DeMayo was a senior. School President Tom Nunan Jr. said the case did not involve any other students, happened off campus and did not pose a threat to the school community. Counselors were made available Friday and again Monday.
The arraignment in Salem District Court added another layer to the case by focusing on DeMayo’s mental condition. Judge Joanna Rodriguez first ordered that he be evaluated before the hearing moved forward. Dr. Joyce Perrotta, a state forensic psychologist, told the court she interviewed DeMayo for a little more than an hour with his lawyer present and also spoke with family members. Perrotta said he showed depressive symptoms, including restricted affect, anhedonia and suicidal ideation, and that those symptoms appeared to have existed for some time. She said he had an adequate understanding of the proceedings but raised concerns about his rational understanding and how his current condition could affect legal decision-making. Perrotta recommended a further evaluation of both competency and criminal responsibility at Bridgewater State Hospital, and Rodriguez agreed. DeMayo pleaded not guilty to murder and armed home invasion, was ordered held without bail and was sent to Bridgewater for further assessment. His attorney did not object in court. The judge also impounded case records by agreement of both the prosecution and the defense. DeMayo is due back in court April 1 for a probable cause hearing.
The scenes described by witnesses in Lynn and Danvers have left a blunt picture of fear, chance and loss. O’Brien said the man with the knife made eye contact with her before she went inside and called 911. Another Lynn resident, Rhonda Deparolesa, said she saw him near her home, and her husband noticed what looked like blood on a large knife. She said he tried her door, but it was locked. John Bossi, who lives nearby, said a home camera captured a car traveling over rocks and through woods behind his house before the suspect was seen on foot in the neighborhood. In Danvers, women who gathered outside Swallow’s home on Friday hugged, cried and stood quietly beside a growing memorial. That contrast has become the emotional center of the case: a nurse known for care and routine, killed inside her own home, and a teenager from another town accused of choosing the house for no known reason. For investigators, the main facts now rest on alleged confession statements, physical evidence, phone data and whatever the psychiatric review may add in the weeks ahead.
As of Sunday, DeMayo remained held without bail while undergoing evaluation at Bridgewater State Hospital, and prosecutors were still describing Swallow’s killing as a random attack. The next key step is his April 1 court return, when the case is expected to move into a more detailed pretrial stage.
Author note: Last updated March 15, 2026.