Montreal police have arrested 15 students at Jeanne Mance High School in the city's Plateau Mont-Royal district. They face charges of drug trafficking.

Police say the students were selling small amounts of marijuana and LSD at the school.

Eight of the students arrested are girls, seven are boys. All but one are minors.

Police spokesperson André Durocher calculates about a quarter of the students at the school were consuming drugs.

"They were selling dope at the school, and obviously some students were consuming the drug. The 15 people that were arrested, all had about 20 customers, so when you multiply, it gives you about 300 students who were consuming drugs. Out of about 1,300 students that are at that school," Durocher says.

Police suspect the drugs were being supplied by an organized biker gang. The students will be transferred to other schools.