A man accused of murder has been taken into custody after allegedly guiding police to a body buried beneath his Massachusetts garage. Authorities believe the remains could be of a female friend who disappeared over a year ago, according to officials.

Shawn Sullivan, 40, became a suspect after reportedly admitting to a friend that he had shot and buried a woman named “Jill” in January 2025. This coincides with the last known sighting of Jill Kloppenburg, Middlesex County District Attorney Marian Ryan revealed to the press on Monday.

Investigators employed ground-penetrating radar to locate an anomaly beneath a “large patched area” in the garage of Sullivan’s family home in Tyngsborough, roughly 28 miles from Boston, as per the DA’s office.

Upon excavation, they uncovered human remains wrapped in a plastic bag.

While the remains have yet to be officially identified as Kloppenburg, authorities are optimistic that the find will provide closure for her family. An uncle of Kloppenburg stated that investigators are “100% positive” the remains belong to her.

Sullivan faces charges including murder, assault and battery with a dangerous weapon resulting in serious injury, and improper disposal of a body.

He was friends with the 47-year-old missing woman, who “had been in his home and … had allegedly been with her around the time of her disappearance,” the DA said.

Kloppenburg, 47, was last seen leaving her home in Lowell, Mass. on Jan. 2, 2025 and has not been seen or heard from since. She was reported missing to Tewksbury Police in Feb. 2025, according to the FBI’s missing persons database.

Before she was reported missing, Kloppenburg’s friends had not physically seen her since Aug. 2024 or spoken over the phone since Nov. 2024, according to Ryan. Her last known activity on her phone was Jan. 14, 2025.

A longtime friend who has been desperately trying to find Kloppenburg was horrififed to learn of her apparent ending.

“You don’t throw her away,” Ann Matlosz told Boston 25 of the alleged killer. “You don’t throw anybody away. They don’t deserve that… Like why? Like how little of a man are you?”

Kloppenburg’s uncle, Steven Kloppenburg, posted on Facebook that he was told investigators “were 100% positive the remains were hers though they still have to confirm it with DNA and an autopsy…”

“She’s been missing for 14 months and has probably been out there for the whole time,” he wrote, according to CBS News.

Kloppenburg’s family told the outlet that they can “now focus on justice and healing.”