Updated

A two-year undercover operation that led to indictments against 15 people for illegally trafficking eagles and other migratory birds uncovered what one prosecutor called a "chop shop" for eagles.

The case in federal court in South Dakota offers a rare window into the black market for eagle feathers, parts and handicrafts, including one alleged dealer who called himself the "best feather man in the Midwest."

Dan Rolince is U.S. Fish and Wildlife's regional law enforcement chief. He says the illegal trade has been a persistent problem. But he expects the new case to be among the largest his agency has handled as more charges are added.

He says it's difficult to determine the size of the market, but the trade is sufficiently prevalent that investigators made the case quickly.