Natrona County High School went into a lockdown on Tuesday morning due to a report of a weapon on campus, school officials said.
The lockdown was a "precautionary safety measure," the Natrona County School District said in a statement. It ended shortly before 10 a.m.
Law enforcement officers were at the school and students and staff are safe, the district said.
Park and Cottonwood elementary schools and Dean Morgan Junior High were on lockout status due to the situation at Natrona County High.
During a lockdown, students are in their rooms with the door locked. Door a lockout, the building itself is locked, but business is proceeding as usual inside.