COLUMBUS, Ind. — Additional bones that are likely human have been found at a south-central Indiana construction site where previously unearthed human bones are believed to be thousands of years old.

Researchers with the University of Indianapolis are analyzing both human and animal bones first found in May during work on the site of a new Bartholomew County judicial building in Columbus.

The small amount of additional bones found there within the last month are believed to be human, said Heather Pope, the city’s redevelopment director.

University of Indianapolis researchers believe that, based on their findings, no bones are now left at the site in the city about 50 miles (80 kilometers) south of Indianapolis.

Bones were first found there on May 18 by construction workers trying to locate a 1940s-era clay sewer line as part of the court services building project, The Republic reported.

The Indiana Department of Natural Resources is investigating the bones’ discovery.

Rachel Sharkey, a research archaeologist with the DNR’s Division of Historic Preservation and Archaeology, said some of the human bones are believed to be from the Native American people of the Adena culture, which existed in the Ohio River Valley as far back as 1000 B.C.

“We haven’t found a lot of diagnostic artifacts to give a definitive time period, but there are some indicators that they are dating to what we like to call the Woodland Period,” Sharkey said.

That period, she said, dates from about 1,000 B.C. to 1,200 A.D.