HONOLULU -- A federal investigation is underway to determine whether ancient Hawaiian artifacts are being sold as antiques on the black market.

The artifacts in question may have been at the museum until the late 1990s, according to Bishop Museum.

About five years ago, the items were repatriated to a native Hawaiian group that oversees the care of ancient remains. The group told the museum it was going to re-bury the artifacts in a cave on the Big Island.

However, the items appear to be on sale.

"I was extremely surprised. It was kind of a shocking thing to hear. The intent of repatriation of objects to any organization or group was never intended for this type of thing to happen," Desoto Brown, of the Bishop Museum, said.

Officials say Bishop Museum is not being held liable for any of the artifacts, but is cooperating with the investigation.