UPDATED STORY: Dixon High School shooting: Shooter is former senior, recently expelled

DIXON – A 19-year-old former Dixon High student is in custody with a non-life-threatening gunshot wound to the shoulder after bringing a gun to the school this morning.

The man shot at school resource officer Mark Dallas, who returned fire around 8 a.m., Sheriff John Simonton said.

The shooting happened in the gym, where seniors, whose last day of school was Friday, were gathered for graduation practice, City Administrator Danny Langloss said.

The officer was not injured, nor was anyone else, Langloss said.

Dixon Police believe that the suspect acted alone and that there is no further threat to the safety of students or staff.

"We're lucky the officer was there. His brave actions saved a lot of lives," said Langloss, whose daughter was among the seniors in the gym.

All Dixon schools are on lockdown while the investigation proceeds. Peoria Avenue is closed.

Dixon High parents can pick their children up at the baseball field at Page Park; bring an ID.

Further information will be released as it becomes available. A news conference will be held at 11 a.m. near Peoria Avenue Bridge.