In an email to parents, Principal Natasha Rowell explained the situation began with an altercation Wednesday. Police worked with school staff and they believed things were well under control until the fight at dismissal time Thursday.
Because of the violence, Green Bay police decided to step up patrols in and around the high school Saturday night during a student dance. Rowell said increased security measures at Preble could go on for weeks.
"We believe that this disturbance was as a result of an ongoing community conflict that spilled over into our school," said Rowell in the email. She did not elaborate on what that conflict might be.
The Green Bay Area Public School District and Police Department will be holding a news conference Monday at 10 a.m. to discuss the situation.