Investigation is under way in Oregon into the killing of six sea lions. The bodies of the federally protected animals were found dead in open traps on the Columbia River.

Federal investigators said the sea lions were gunned down. The shooter killed four California sea lions and two Steller sea lions. Their bodies were found in traps early Sunday afternoon.

"We're really shocked. We're a nation of laws, and we should expect people to abide by them," said Sharon Young, a Humane Society spokeswoman, according to The Associated Press.

This comes just a day after authorities found three elephant seals shot at a breeding ground in central California and less than two weeks after a court issued a temporary injunction against authorities killing the salmon-gobbling mammals.

Authorities said the investigation will try to determine whether there is any connection between the killing of the six sea lions and shooting of the three elephant seals.

Investigators said they planned necropsies for the six sea lions. The area were the carcasses were found - below the Bonneville Dam on the Columbia River on the border of Oregon and Washington.- was sealed off and it’s treated like a crime scene by state and federal agencies.

The gunman might have been from the Washington side, said Brian Gorman, a spokesman for the National Marine Fisheries Service.

The states of Washington and Oregon have federal authorization to capture as many as 85 sea lions per year. The authorization was contested and brought to court by the Humane Society of the United States.

Until the ruling of a lawmaker no animals may be legally killed.
The next hearing was scheduled for May 8.