Up to nine bears have been spotted in the park. Washington State Parks says this is mating season, which makes them extra territorial, and five male bears are fighting with one another.
A park spokesperson says the park closed last week because visitors were not backing away after the bears made threatening moves toward them.
Washington State Parks is working with the Yakama Indian Nation to relocate the bears.
There is no set date for when the park might reopen, but a spokesperson said it could remain closed until September.