Prosecutors Thursday considered charges against senior girls who punched, beat and battered junior girls at the "powder puff" game last Sunday at Chipilly Woods, a county forest preserve.
The younger girls were pelted with fish guts, condiments, blood and excrement, had raw Spam crammed in their mouths, were forced to eat pig intestines and taste paint thinner and had buckets placed over their heads that were pummeled with baseball bats, officials said.
Five girls were hospitalized. One with a broken ankle, another required 10 stitches to close a deep scalp cut and the others were treated for bumps, bruises and abrasions.
Hazing is part of the yearly tradition but this year it got out of hand.
Police, parents and school officials had identified more than 50 of the 100 girls involved in the incident from videotapes and photographs taken by male students who attended the event.
Adults who provided beer to minors could face criminal prosecution, a school board member said.
"There's a lot of alcohol involved beforehand," Jenni Stasi, a former Glenbrook North student who participated in past games, told "Good Morning America."
Stasi said junior girls know they might be hazed and pelted with food when they sign up for the faceoff against the seniors.
"They know about it. It's been going on for 20 years and it's happened the same way every year," she said.
Videotape of the melee originally broadcast by WMAQ-TV, Chicago, was shown on NBC and local stations, and picked up by stations in Europe and around the world. About 15 television trucks were parked at Glenbrook North Thursday morning setting up cameras.
Three of the victims retained a lawyer to who plans to file a lawsuit.
"When you rent a keg, or get a keg, people can find out who bought the keg. I wouldn't want to be those parents," Rollin Soskin, a personal injury attorney, told WFLD-TV. "They know who attacked them. They know who hit them. As they watched the tapes they're surprised, I think, by some of the people who held them down, or jumped on the bandwagon. But they can see who the primary perpetrators were ..."
The game between senior and junior girls is a decades-old tradition at the high school in Northbrook, an affluent suburb north of Chicago, and the hazing was seen as sort of a rite of passage for underclass girls.
"We were supposed to be hanging out and playing football," one of the injured girls told the Chicago Sun-Times. "We knew we'd get a little pain, but nothing bad."
Some girls wore their own $40 jerseys made for the game at school Friday. In the past police have been notified where the game would be played but last weekend the girls kept the off-campus site top secret, communicating by e-mail and cell phones at the last minute.
Northfield Township District 225 officials said the game was off-campus and played without their knowledge. School officials were investigating what disciplinary action they could take.
"It was supposed to be a friendly initiation into our senior year," said a 17-year-old junior. "I got hit over the head with a bat or a bucket." Other girls said they were surprised to see people drinking beer from a keg getting really drunk.
"About 10 minutes into it, the mood completely changed," said Marina. Her earrings were ripped from her ears but she said some senior girls pulled others off her and tried to stop the beatings.
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