LOWELL, Mass. — Middlesex DA Marian Ryan announced on Monday that human remains found in the home of a Tyngsboro man are believed to be those of missing woman Jill Kloppenburg.
[ Friends fear the worst for Lowell woman missing since January ]
Jill Kloppenburg, 47, disappeared back in January of 2025. Her friends told Boston 25 back in October that they were fearing the worst.
According to the FBI, Kloppenburg was last seen leaving her residence on Broadway Street in Lowell.
“We’re very concerned because she hasn’t checked in. No matter what is going on in her life, she has always checked in with her friends,” Ann Matlosz told Boston 25.
According to the DA, on March 10, the Nashua, New Hampshire Police Department received a call about a possible homicide.
The friend of a man named Shawn Sullivan told police that Sullivan had confided in him by telling him that he had killed a woman by the name of Jill around January of 2025.
Sullivan further claimed he shot and buried her under the floor of his garage on Audrey Avenue in Tyngsboro.
Nashua, New Hampshire Police took that information and was able to see that there was a missing person in Tyngsboro by the name of Jill Kloppenburg.
The individuals who made the missing person report to Tyngsboro Police claimed to be friends of hers, and they had not physically seen her since August of 2024 and their last contact with her via text was in November.
Last record of any communication from her cell phone was on January 14, 2025, according to the DA.
Based on the investigation, Kloppenburg was someone known to Sullivan, as she allegedly had been in his home before. He had also allegedly been with her around the time of her disappearance.
On Sunday, March 15 Tyngsboro Police, Massachusetts State Police, and Tewksbury Police executed a search warrant on that house and observed in the garage of the home a large, patched area about 5 feet long and 3 feet wide.
Using ground penetrating radar to scan, something was located.
The Chief Medical Examiner was able to confirm that after cutting through the floor, human remains were recovered in a bag, however they have not been officially identified at this time.
Middlesex District Attorney Marian Ryan said they do believe the remains are in fact those of Jill Kloppenburg.
Shawn Sullivan, 40, will be charged with murder, assault and battery with a dangerous weapon causing serious bodily injury, and improper disposal of a body. The Chief Medical Examiner is also working to determine a cause of death.
The investigation is ongoing and active at this time, according to the DA.
Anyone with information is encouraged to contact Massachusetts State Police at 781-897-8300.
In a statement following the press conference, Tewksbury Police Chief Ryan Columbus wrote that this was not the outcome anyone had hoped for, but they were grateful Jill’s family and friends had some answers, peace, and closure. They also offered their condolence to her loved ones.
“For more than a year, members of our Criminal Investigation Division continued working this case and followed every lead in an effort to find Jill and determine what happened. Their persistence and commitment in this case are just one example of the dedication our officers bring to serving this community every day,” he said.
The statement continues:
“I also want to recognize Detective Timothy Oteri, whose work was central to this investigation. Detective Oteri listened carefully, gathered critical information, and diligently pursued every lead in the effort to locate Jill and bring clarity to this case. The Town of Tewksbury is fortunate to have dedicated professionals like Detective Oteri and the members of our Criminal Investigation Division, who remain committed to seeking the truth and supporting victims and their families. We are grateful for the partnership of the Middlesex District Attorney’s Office, the Massachusetts State Police, the Lowell Police Department, and the Tyngsborough Police Department. Their support was essential throughout this investigation. A suspect is in custody, and we trust the legal process will take its course.”
— Chief Ryan Columbus
The Tyngsboro Police Department also released a statement following the news of the discovery, recognizing the work of the investigators in the case whose “collaborative efforts” led to the arrest of a suspect and brought a level of closure to Jill’s loved ones. The departments involved in the investigation included the Tyngsboro Police Department, the Tewksbury Police Department, and Massachusetts State Police.
The statement further says:
“This case represents a tragic loss of life, and our thoughts remain with the victim’s loved ones during this incredibly difficult time. I want to reassure our community that the suspect is in custody, that this incident was not a random act of violence, and that there is no ongoing threat to public safety. We understand this case is of great concern to our community. This remains an active investigation, and additional information will be released by the Middlesex District Attorney’s Office as it becomes appropriate.”
— Chief Shaun Woods
Neighbors on Audrey Avenue woke up Sunday morning to an active investigation.
“I woke up to my parents being like, ‘Oh my God,” said neighbor Ella White. “It really is crazy knowing this happened so close to home.”
Monday afternoon, Boston 25 saw a man going into the home.
“You don’t know what you’re talking about,” the man yelled to reporters.
Meanwhile, family and friends of Kloppenburg were still coming to terms with the news.
Ann Matlosz has been searching for her high school friend since she disappeared over a year ago.
“You don’t throw her away,” she said over the phone. “You don’t throw anybody away. They don’t deserve that... Like why? Like how little of a man are you?”
Boston 25 crews also saw police going into the home Monday night.
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