OKLAHOMA CITY (AP) - An investigation into grade tampering at an Oklahoma City school has led the school district to place the principal on administrative leave.

The district announced Wednesday that Douglass Mid-High School Principal Brian Staples was placed on leave with pay.

A woman who answered a phone number listed for Staples said Staples was not at home before hanging up.

The district says an investigation began in June following allegations by students and former employees of grade tampering.

A statement by school district deputy Superintendent Sandra Park said ``a majority of the allegations were unfounded.'' The district declined further comment.

The statement says an independent investigator conducted the investigation for the district.