>> reporter: and 60, illinois, hometown of ronald reagan, matthew milby walking to school at 8:00 with a semi automatic rifle moving towards the gymnasium where seniors gathered for graduation rehearsal. as he walked the halls he opened fire. school resource officer mark dallas pulled his weapon and confronted the shooter. the suspect turned and ran, officer dallas gave chase, they exchanged gunfire. police say the suspect was struck at least one time that his injuries are not life-threatening. the only indication is the response to officer dallas was textbook perfect. >> i cannot be more proud of the police officers, the way you responded to the situation, saturating the school, we confronted the suspect head on. because of his heroic action countless lives were saved was we are indebted to him for his