ST. LOUIS COUNTY, Mo. – The Mehlville School District has lifted lockout orders for three grade schools in the district.

Trautwein Elementary School, Hagemann Elementary School, and Washington Middle School had been on lockout Monday afternoon due to unspecified police activity in the area.

The lockout was lifted after approximately 20 minutes.

According to a statement from the district, “A lockout is used when there is police activity near a school campus. During a lockout, any students outside at PE or recess quickly return to the building. All exterior doors are locked and nobody is allowed to exit the building.”

Earlier in the day, Mehlville High School was placed under a lockdown.