A 15-year-old girl is under arrest following a knife attack in Beaconsfield Wednesday that led to Beaconsfield High School being placed on lockdown.

The arrest was made after a fight broke out between two teenaged girls over the lunch hour at a strip mall near BHS.

The incident took place shortly after noon across Highway 20 from the school in Elm Plaza, at the intersection of Elm Ave. and Fairway Dr.

“There was a conflict that happened during class before lunch and there was supposed to be a fight because of it, but only a fist fight,” said a teenaged witness, who CTV is not identifying.

The fight soon degenerated into an armed attack.

“She ends up pulling out a knife on the girl and then tries to stab her in her gut,” said the witness.

“They started fist fighting. The knife was just waving around everywhere. And then as soon as I saw that, my first instinct was to run and get the knife away from there,” she said.“So I ran in and I grabbed the girl who had the knife and I was holding on to her arm while they were still fighting each other.”

Once the girl with the knife had been disarmed, the teen who had been attacked collapsed to the ground, bleeding profusely from the face, said the witness.

“She started bleeding and she almost went unconscious. And then I screamed out for someone to help me. One of my friends got my sweater and put it on her forehead to stop the bleeding and then paramedics were called. Police were everywhere,” she explained.

Beaconsfield High School, a short distance away from the strip mall via a footbridge, was put on lock down, according to students, for about an hour because school officials unsure where the girl who had the knife had fled.

“After the fight, I ended up picking up the knife and throwing it into the garbage can. The girl that had the knife ended up running away,” the witness said.

A short time after speaking with the witnesses, Montreal police arrested a 15-year-old suspect.

The victim suffered minor injuries.

BHS is located south of Highway 20 in Beaconsfield, and has about 900 students.