Police are treating it as a death investigation, but the area of the discovery is a known burial ground for Native Americans.

(CBS) – A gruesome discovery in Riverside.

Construction workers Thursday afternoon uncovered human bones in the 100 block of Bloomingbank.

Police are treating it as a death investigation, but that area is a known Indian burial ground. Remains have been found there before.

The remains were found in the 100 block of Bloomingbank in Riverside by a sewer pipe replacement crew.

Police Chief Tom Weitzel said the first officer on the scene confirmed the skeletal remains were human.

“You could clearly see part of the skull, jawbone and teeth,” he said.

Chief Weitzel said a medical examiner investigator on-the-scene determined the bones were not put in the ground recently and foul play is not suspected.

He said the ME investigator and detectives from the West Suburban Major Crimes Task Force determined “they’re old bones” and that the site was “not a fresh dig”.

“That area is a well-documented American Indian native burial ground in the 1830s,” Weitzel said.

In addition to possibly being the remains of a Native American, Weitzel said it’s also possible the remains were of an early settler to the area. He said a pioneer’s remains were found 15-to-20-years ago along that same block, next to the Des Plaines River.

A forensic anthropologist with the ME’s office will determine whether either is the case. That could take a few months.

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