Japanese authorities confirmed a dock that washed onto Washington state's shores last month came free from the coast of Japan during the 2011 tsunami.

A crew removed 400 pounds of marine plants and animals from the dock's remains to keep invasive species from taking hold.

The dock was found within Olympic National Park and the Olympic Coast National Marine Sanctuary.

The dock is similar to another one that washed ashore in Oregon last summer (AP/Washington Post, Jan. 17). -- MM