John and Irina Walker are accused -- alongside 16 other suspects in Oregon and 10 in Washington -- of operating the illegal gambling business and unlawful fighting ventures, The Oregonian reported Thursday.
The indictment alleges the derbies featured dozens of cockfights in which knives and other cutting instruments were attached to the legs of roosters fighting to the death, the newspaper said.
"Besides being a barbaric practice, cockfighting jeopardizes public health and safety and facilitates the commission of other criminal acts," said U.S. Attorney Amanda Marshall. The "fairly large-scale cockfighting venture" also supported illegal gambling, she said.
Irina Walker is Romanian King Michael I's third daughter and is sixth in line to the throne. She was born and raised in Switzerland and moved to Oregon in 1983, The Oregonian said.
The Walkers were charged with conspiracy to violate the Animal Welfare Act and could face a maximum sentence of five years in prison and a fine of $250,000 each, the Justice Department said.
The Walkers were scheduled to appear before a federal magistrate judge Friday in Portland, CNN said.