Dixon, IL, school resource officer Mark Dallas has been named the 2018 IACP/Target Officer of the Year. On Wednesday May 16, Officer Dallas was assigned to Dixon High School when he confronted a gunman.

Matthew Milby Jr., 19, is accused of entering the school and shooting at physical education teacher Andrew McKay in a hallway outside the gym where the seniors were gathered to rehearse their graduation ceremony. McKay warned the students and told them to flee.

Seconds later, Dallas left the athletic director’s office and began chasing Milby, according to Illinois State Police. The teen ran toward his car and fired shots toward Dallas who returned fire, striking Milby in the right hip and right shoulder, the State Journal-Register reports.

Other finalists for the award included Officer Taylor S. Rust of Plano, Texas, Sgt. Luis Celis of Doral, Florida, and Nathaniel Dawson of the Washington State Patrol.