RIVERSIDE, Ill. (STMW) – Police were called to a west suburban high school twice on Monday to quell disturbances — one of which involved “offensive postings” on a social networking site — and arrested three teens, one of whom had a knife.

The incidents occurred at Riverside Brookfield High School at 160 Ridgewood Rd. in Riverside, according to Riverside police.

In the first incident, a 17-year-old from North Riverside was arrested for unlawful use of a weapon, battery and aggravated assault, according to a report from police. The student, who had a knife, threatened another juvenile with bodily harm, police said. The knife was displayed, but was not used.

In the second incident, two male juveniles got into a fight in a school hallway after learning of the earlier disturbance involving the knife. Offensive postings had been made on a social networking website between the combatants, police said. Both were charged with battery and disorderly conduct.

Police personnel worked directly with school staff to quell the disturbances, police said. School staff acted immediately to apprehend the offenders and contacted police immediately.

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