A dozen high school students were expelled for an on-campus brawl over who got invited to a party, a fight school officials said was arranged on the social-networking hub MySpace.com.

The school board in this St. Louis suburb voted unanimously Monday to expel the Edwardsville High School students through the end of the school year for the Nov. 9 melee. Three were seniors who were barred from graduation ceremonies next spring, Superintendent Ed Hightower said Tuesday.

No one was seriously injured in the fight involving 11 girls and one boy.

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Two groups of students had been squabbling for a month about who had been invited to the party, and administrators had been working with them and their parents to avoid a conflict, Hightower said.

Seven students agreed in writing Nov. 6 to stop "disrespecting" each other, keep to themselves and report problems to adults. The students were told they faced police involvement or "exclusion" from the school if they broke the pact.

Just two days later, Hightower said, students posted MySpace messages finalizing plans to fight the next day. The fight ensued as planned in the high school's commons area, Hightower said.

"There were numerous interventions, numerous opportunities for these students to resolve their differences," but they chose to fight instead, Hightower said.

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MySpace is grappling with ways to curb the use of the site for such purposes, distributing a guide for school administrators and "letting them know that anything that can happen on a school playground also can happen online," said MySpace's chief security officer, Hemanshu Nigam.

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