Bond for Thomas Scott Barfield was set Tuesday at $20,000. He remains in the Fort Bend County jail on a charge of possession of a prohibited weapon.
About 4,000 students at Seven Lakes High School in Katy were evacuated Monday. Katy school officials initially said a "potential explosive device" was found, and later explained the device was a zip gun. The district described a zip gun as "any device altered to propel an object designed to cause harm." Police later found a firearm in the trunk of Barfield's vehicle.
Classes at Seven Lakes resumed Tuesday.