A 15-year-old boy was in police custody Tuesday in connection with the outside that forced the school into lockdown.
Joliet police say the incident involved two boys, one of whom was chasing the other with a gun, according to a story in the Joliet-Herald News.
The incident began at about 4:05 p.m. Monday when a Central staff member heard a shot, resulting in the school going into lockdown for about 30 minutes. No one was injured and the lockdown was lifted at 4:40 p.m.
No other details were available on the altercation. Calls to the were not returned.
Editor's note: An earlier version of this story had an incorrect age for the teen who is in custody.