The latest local news, weather and high school sports in and around Columbia and Jefferson City

(AP) -- COLUMBIA, Mo.-- The Columbia school district plans to strengthen security Friday at its high schools after a spate of rumors have raised safety concerns.

In a letter send home to parents Thursday, Superintendent Chris Belcher said all high schools will be closed campuses Friday. Students won't be allowed to leave for lunch or other activities without a "demonstrated academic need." Also, students will be able to enter and leave only through designated doors.

The letter also said that rumors of possible violence have been "thoroughly investigated and found to be false."

Still, Belcher noted that some students have been unsettled by last week's killings at Sandy Hook Elementary School and by doomsday scenarios purportedly based on the Mayan calendar.

To reassure students and parents that schools are safe, more police will patrol near the schools.

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