An airline employee in Arkansas peeked into an otherwise unremarkable container last week and made a surprising discovery: Parts of human heads.

Now authorities in Arkansas have launched an investigation after four human heads and 40 partial heads were seized at Little Rock National Airport, apparently bound for a Medtronic facility in Texas for use in medical training.

Medtronic spokesman Brian Henry said the heads were supposed to be used for physician training at the Fridley-based company's ear, nose and throat surgery division in Fort Worth.

"It's very common for us to receive shipments of materials for medical research and education," he said. It's uncommon for such a mistake to occur, he added.

Henry believes the heads, which he described as "four cranial samples and 40 temporal lobes," were mislabeled by the vendor, causing the mix-up.

A Southwest Airlines freight employee reportedly discovered the heads June 9 in several containers and immediately notified authorities.

"Our employee did the right thing," said Southwest spokeswoman Olga Romero, who declined to comment further.

Garland Camper, coroner of Pulaski County, Ark., told Reuters the heads "were basically in plastic containers with lids that are not air-sealed. They were duct-taped with minimal information to disclose what was inside.

"Since then, we have learned that the paperwork that we have asked for does not quite meet the same description of the specimens that we have," Camper said. "So we've got some discrepancies there."

He said he wants to confirm that the heads were not being shipped as part of a black-market ring for human body parts, and the shipment remains at the county coroner's office until the investigation is complete.

The vendor, JLS Consulting of Conway, Ark., could not be reached for comment Thursday. However, JLS founder Janice Hepler told an Arkansas newspaper that the company is cooperating with the coroner's investigation.

Hepler describes herself on the company's website as having more than 25 years' experience in the medical industry, including 15 in surgical nursing and 10 in "medical education and research program management."

The company's site also has a reference from a Medtronic official that states, "Hepler is an expert in the management of cadaver programs."

This isn't the first time Medtronic has been on the periphery of a grisly drama in recent years.

In 2005, regulators shut down a New Jersey company called Biomedical Tissue Services Inc., which authorities claimed ran an illegal cadaver ring with the help of several New York City funeral homes that provided body parts from the dead.

Among them: "Masterpiece Theatre" host Alistair Cooke.

A Medtronic subsidiary called SpinalGraft Technologies was supplied with bone grafts from the cadavers through a Florida company called Regeneration Technologies.

That company processed tissue from Biomedical Tissue Services that was later recalled by the Food and Drug Administration. The bone grafts were made into dowels, plugs, chips and powder that were distributed by SpinalGraft Technologies for use in spine surgeries.

Janet Moore • 612-673-7752