Clatskanie students were released early Wednesday after the Middle High School went into a lockdown around 1:30 p.m., according to the school's Facebook page.
Elementary, middle school and high school students were evacuated at about 2:30 p.m.
The school district canceled all activities scheduled for Wednesday.
This was the second lockdown in two days, according to reports from The Clatskanie Chief. On Tuesday, a threatening message was discovered in one of the girls' bathrooms at the high school, according to The Chief.
Columbia County Sheriff's deputies continued to search the school after the lockdown was lifted, The Chief reported.
Further details were not immediately available.
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