'Heartbreaking:' Tennessee authorities believe to have found remains of missing 15-month-old Evelyn Boswell

BLOUNTVILLE, Tenn. -- The Tennessee Bureau of Investigation announced Friday night they believe they have found the remains belonging to missing 15-month-old Evelyn Mae Boswell.

Boswell was last seen in December 2019, but she was not reported missing until February.

WJHL reports TBI and detectives with the Sullivan County Sheriff's Office searched a property belonging to a family member of Evelyn's mother, Megan Boswell, in northeast Tennessee.

Authorities said they found the possible remains of the 15-month old there.

WATCH: Tenn. Bureau of Investigation gives briefing after remains believed to be Evelyn Boswell found

"At this time, the investigation is still in the very early stages," Sullivan County Sheriff Jeff Cassidy said during a news conference Friday night. "There is a lot of work left to be done."

The TBI said an autopsy is pending and the investigation is ongoing.

In late February, investigators searched a mobile home park in Sullivan County, Tennesee, in connection with her disappearance.

A few days before, authorities searched a pond in Wilkesboro, North Carolina. That search proved "inconclusive."