Bones believed to belong to three children were undergoing DNA testing to determine whether they belonged to long-missing young brothers from Michigan. A box, containing bones and teeth, was found in a shed in Montana in September.

An anthropologist who reviewed the bones estimated they belonged to three children between the ages of 2 and 4, 5 and 8 and 6 and 10, the Detroit News reported. Authorities were working to determine whether the remains were connected with the disappearance of three brothers, aged 5, 7 and 9. The brothers, Andrew, Alexander and Tanner Skelton, went missing from Michigan in 2010.

“While it’s very interesting and something we’re following up with big time, we haven’t seen any other connections [that would link the cases],” said State Police Det. Lt. Jeremy Brewer, according to USA Today.

The National Missing and Unidentified Persons System at the University of North Texas Center for Human Identification was performing the DNA testing. It was expected to take anywhere from three to six months, according to The Missoulian.

“We’ve gotten over 2,000 tips on [the missing brothers] case,” Brewer said. “We’ve had several tips over the past several years that have been [about] human remains and bone…but more often than not, they have been prehistoric bones or Native American bones.”

No arrests had yet been made in connection to the findings. A man who previously lived in the home where the bones were found was interviewed but not detained. Doug Labare told police he did not recognize the box and did not know whether it was put there while he lived there or after, The Missoulian reported.

Police still did not have a concrete answer about what happened to the Skelton brothers. The three children were last seen with their father, John Skelton, who police said never gave them a sufficient answer for what happened. Skelton told authorities he “gave the boys to unknown individuals.” He is serving 10 to 15 years behind bars for unlawful imprisonment.

“There has been nothing previously reported to police linking the brothers to Montana and it is not known at this time if the remains are from related siblings,” state police said in a statement. “Until the testing is completed and additional investigation by law enforcement in Montana occurs, it cannot be determined if these remains belong to the missing Skelton brothers.”