BUHLER (AP) — Security was increased at a central Kansas high school after police say a threat was found on a bathroom wall.

Classes are going on as usual Friday at Buhler High School but police officers are at the school as a precaution.

KWCH reported Superintendent Michael Berblinger says a message found at the school Thursday was vague but it mentioned April 25th.

No other details about the message were released. No one has been arrested.

Students entering the school Friday morning were allowed to enter only through the main door and could not carry book bags. Police searched other bags, such as purses, which had to be left in lockers.

Buhler police chief Bill Tracy says officers will be at the Reno County school all day.