PORTLAND, Ore. (AP) - Officials say the traps in which six Columbia River sea lions apparently were shot to death had been closed.

Wildlife agents have been trapping sea lions that eat salmon at Bonneville Dam.

On Sunday, six were found dead. They are protected by federal laws.

At first, officials assumed that the traps were open.

In the trapping operations, the traps are left open so the sea lions get used to them. When wildlife agents are ready to remove the sea lions, they close the traps.

But Brian Gorman, of the National Marine Fisheries Services, says that when officers got to the carcasses near an island below the dam, they found the traps closed.

The trapping operation has been suspended while an investigation of the deaths is conducted.

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