LOWELL, Mass. — Investigators now believe the body recovered from beneath the floor of a Tyngsboro home is that of Jill Kloppenburg, a Lowell woman who has been missing since January 2025.
On Monday, Boston 25 News spoke with one of Kloppenburg’s close high school friends, who said she was heartbroken by the news that the remains believed to be her friend had finally been discovered after more than a year.
Investigators search Tyngsboro property
On Sunday morning, residents on Audrey Avenue watched as investigators moved in and out of the home where the remains were found.
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Middlesex District Attorney Marian Ryan announced during a Monday afternoon news conference that police were led to the property after receiving a tip from a man who claimed his friend had confessed to killing a woman named “Jill” last year and burying her under the garage floor.
When investigators dug into a patched section of the floor, an area about 5 feet long and 3 feet wide, they discovered a body hidden inside a bag, according to Ryan.
While the Chief Medical Examiner is working to identify the remains officially, Ryan said they do believe the remains are in fact those of Kloppenburg.
The Chief Medical Examiner is also working to determine the cause of death.
Kloppenburg missing since early 2025
Kloppenburg disappeared in January 2025. Friends of the 27‑year‑old told Boston 25 News that after months of searching and no sign of her, they had begun to fear the worst.
On Monday night, we spoke with one of those friends about the arrest that came roughly 14 months after Kloppenburg vanished.
Friend shares raw emotion
“You don’t throw her away. You don’t throw anybody away. They don’t deserve that,” Ann Matlosz told Boston 25.
Matlosz continued, “Like, why? Like, how little of a man are you? She was five‑fraking-two and a half, and like 120 pounds, maybe if that, soaking wet. Like, really? You shot her?”
Matlosz said she hopes the arrest will finally bring justice and bring closure to all who cared about Jill.
Suspect set to face a judge
The suspect in the case, 40‑year‑old Shawn Sullivan, is scheduled to appear in Lowell District Court on Tuesday, according to Ryan’s office.
He is expected to face charges including murder, assault and battery with a dangerous weapon causing serious bodily injury, and improper disposal of a body.
Anyone with information is encouraged to contact Massachusetts State Police at 781-897-8300.
This is a developing story. Check back for updates as more information becomes available.
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