A Dixon Police SUV was towed away from Hall Memorial Park Wednesday after it was riddled with bullets.
Police say an officer and a student at the nearby Dixon High School, exchanged gunfire that morning.
The teen is in custody, and the school is shaken.
"We were very paranoid and scared," student Jose Martinez said.
Martinez and 1,100 classmates were forced into a 40-minute lockdown.
Police say they were tipped off about a student with a gun, believed to be heading to campus with it.
Classmates say the suspect, a sophomore at the school, is no stranger to trouble and was apparently just returning to school after being kicked out.