Federal authorities revealed Wednesday that they raided the home of an Oakdale couple in December and confiscated a variety of rhinoceros and elephant parts that the pair claimed they had collected as family heirlooms.

The U.S. Fish and Wildlife Service launched the investigation in 2016, and it led to a search on Dec. 12 of a home in the 4700 block of Helmo Avenue occupied by Chang Xiong and his wife, Ma Chang.

Search warrant documents unsealed Wednesday in federal court in St. Paul show that investigators seized seven rhino feet, five rhino toenails, a rhino horn and two wine cups, two walking stick handles, a snuff bottle and a ring, all made from rhino parts. They also seized a carved elephant tusk, an ivory figurine and two bracelets and a ring.

Neither Xiong nor Chang has been charged with a crime. Xiong declined to comment Thursday and referred a reporter to his lawyer, Sia Lo, who could not be reached immediately for comment.

The warrant application indicates that authorities suspect Xiong and Chang of violating the Lacey Act, which prohibits the illegal transportation of wildlife and the creation of bogus documents to support the enterprise; the Endangered Species Act, which prohibits importing, exporting or commercial trading of endangered species; and smuggling.

Darin Brandenburg, a special agent with the wildlife service based in Madison, Wis., outlined the investigation in a statement to support the warrant. Brandenburg wrote that it began May 11, 2016, when a source who runs a taxidermy business in the United Kingdom sent U.S. authorities an e-mail indicating that Xiong had tried to buy a rhinoceros foot. He said the source explained to Xiong that it would be illegal to ship the foot to the U.S., but he sent him Brandenburg's covert e-mail address, indicting that he might be able to help.

Brandenburg said Xiong sent him an e-mail looking for rhino feet and continued his pursuit of the contraband even after being told that they had to be careful to avoid getting into trouble. Xiong said he had bought a rhino foot in April 2016 from a seller in Florida without any trouble. They eventually agreed to meet at a Home Depot parking lot in Hudson, Wis., to make a deal.

Xiong and Chang arrived at the lot in July 2016 in a black Mercedes, Brandenburg said. After Chang inspected a rhino foot that was secretly marked with "fluorescent invisible detection paste," Xiong paid Brandenburg $1,100. State and federal investigators followed the couple back to their home in the 1900 block of Montana Avenue E. in St. Paul, where they lived at the time, and watched them unload the foot.

In November 2016, Customs and Border Protection agents intercepted a 24-pound shipment of elephant toenails, bone and two small unidentified animal horns. They released the shipment and it was delivered to Xiong at his St. Paul address.

He arranged another covert sale to Xiong of a rhinoceros foot for $1,100 in September 2017.

"Xiong inspected the foot and said he was going to display it in his house," Brandenburg wrote. "I asked Xiong how many rhinoceros feet he had now. Xiong replied saying he only had the two he had bought from me. … Chang said she had eight relatives so she wanted me to find a rhinoceros foot for each of them. Chang also said she wanted a rhinoceros foot for each of her four children."

Chang, who is from Thailand, explained that rhinoceros parts are good luck. Xiong immigrated to the U.S. more than 20 years ago from Laos. In the Hmong culture, Brandenburg wrote, "rhinoceros parts and elephant ivory are symbols of wealth and prosperity."

Authorities inspected a package shipped to Xiong from the United Kingdom in January 2018 that contained a rhinoceros foot.

Brandenburg said he arranged another sale of two more rhinoceros feet in December for $1,600.

In addition, he said, Xiong bought an elephant tusk through a Canadian auction firm and it was shipped to him with a customs form declaring it as plastic.

Dan Browning • 612-673-4493