District officials say the school remained open all day, there were no reported threats or incidents.
Wichita Falls Police Sergeant Joe Snyder says it started with a schoolyard brawl between two students, while some other kids watched.
Snyder says two juveniles got Class "C" misdemeanor tickets for fighting on Tuesday.
He says police learned the kids were claiming to be in gangs they're actually *not* a part of.
On Wednesday night, graffiti was found on Rider's sidewalk, doors, and windows .
Snyder says the graffiti has been removed.
Renae Murphy, with the school district, says 10 Rider students were sent to Denver Alternative Center as a result of Tuesday's fight.
She says last night, rumors started circulating among students that something might happen today in school.
Snyder says social media -- like Facebook -- spread the information and exaggerated it.
Murphy says there was an increased police presence today at the school.
The rumors apparently led to many students staying home today...
Normal attendance at Rider is 94 percent ... But today it was down to 72 percent.
Murphy says the absences will be treated like any other absence -- meaning, if the students have not exceeded the allowed absentee days and bring notes from their parents on Monday, the absences will be excused... but will still on the record as an absence.
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