The Katy school district announced on its website that Seven Lakes High School was safely evacuated Monday after campus police learned of a "perceived threat." The Harris County sheriff's office responded.
The district about 20 miles west of Houston says the potential explosive was later identified and that a "student suspect is in custody." It did not elaborate.
Students were evacuated to an enclosed area on the baseball and football fields. They were later released for the day and after-school activities canceled.
Messages seeking further details have been left for the district's public information office and sheriff's department.