Four bald eagles, America's national bird, were shot and killed last week in Washington state.
Their bodies were found floating in a lake, The Seattle Times reports.
The birds were probably hanging on some branches when they were shot with a small-caliber rifle, officials told the paper.
It's not clear why the birds were murdered. Bald eagles are usually killed for their parts, such as their feathers and talons, which are sold on the black market for hundreds of dollars.
But in this case the birds were just left for dead.
Bald eagles are protected under the federal Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act, which carry maximum fines of up to $100,000 and $15,000, respectively, with up to one year in prison, according to the U.S. Fish and Wildlife Service.
Investigators are offering a $13,750 reward for information leading to the conviction. The Stillaguamish Tribe, a Native American tribe in the area, contributed $10,000 toward the reward.