YANKTON, S.D. (AP) — The Yankton School District is making changes to its security protocols and systems after 2 men were arrested last week for entering the high school.

The district on Tuesday told parents the front entrances of the schools will now remain locked.

A camera and buzzer were installed at Yankton High School, and now people may only go inside the building if a staff member authorizes the entrance. The same system will be installed at the elementary and middle schools.

The changes come after 18-year-old Joseph Vanbuskirk and 19-year-old Adam Gerard, who are University of South Dakota students, entered the high school Thursday. Police say the men didn't have permission to enter the school and are facing various charges including trespassing and possession of firearms on school grounds.

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