Officials in a Pennsylvania school district where a substitute teacher released pepper spray to break up a student fight chastised her actions, while a union official hailed her as a hero.

Pat Dawson, spokeswoman for the Woodland Hills School District in Swissvale near Pittsburgh, said that Superintendent Stan Herman had decided not to hire substitute teacher Lois Sharlock to teach in the district again.

She said Sharlock violated the district’s zero-tolerance policy on weapon possession by carrying pepper spray into the school March 16.

But Arleen Starr, a representative of the Pennsylvania State Education Association, applauded Sharlock. “You’ve got a situation where she was protecting children who could have been injured by a mob situation,” Starr said.

Sharlock released pepper spray when a hallway fight between two girls spilled into her classroom and other students joined in. Police got reports that as many as 50 students were involved.

Three students were treated and released at Children’s Hospital in Pittsburgh, and up to 25 more were treated for eye irritation by paramedics at the scene.

While the district has a policy prohibiting possession of pepper spray on school property, Starr said substitute teachers rarely see personnel policies.

“That’s fair to say,” Dawson said, adding that substitutes receive policy handbooks that do not necessarily provide details.