(Columbus, OH/AP) — Search warrants are being executed in Ohio Auditor Dave Yost's investigation of alleged fraud by the Columbus City Schools.

A spokeswoman for Yost's office declined to say how many warrants were involved in the Thursday action, but called it "more than a few."

The Columbus Dispatch reports the warrants were served at Walnut Ridge High School on the far east side and from Marion Franklin High School on the south side.

State and federal authorities are investigating Ohio's largest school district over allegations employees improperly altered the grades or attendance records of struggling students to improve performance ratings.

Yost launched the investigation after a request by Superintendent Gene Harris. It has grown to involve several top district staff members.

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