Dixon, IL — At 8 a.m. on Wednesday morning, a former high school student, 19, brought a firearm to Dixon High School as the students were reportedly preparing for their graduation. According to Daily News, the assailant opened fire, which caught the attention of the school resource officer, Mark Dallas. The two fired at one another and Dallas gave chase — soon he shot the shooter and was able to apprehend him.

Once the shooter was disarmed, he was taken into custody where authorities treated his wounds — he is fully expected to survive.

Students and faculty had barricaded themselves into their rooms, using whatever they had to keep the shooter from potentially entering and killing many. By mid-day, students were authorized to exit the school and get back to their vehicles.

Exactly what type of weapon was used is currently unknown.