"Officers […] located four people [who] were arrested for drug-related offences, but as well, they located a quantity of marijuana, cocaine, crystal meth and chemicals to produce crystal meth," Toronto police Const. Tony Vella told the media.
Police have entered the home to remove the potentially dangerous chemicals inside.
About eight homes in the area were also evacuated.
Parents who have children attending the school were asked to pick them up.
About 100 students who haven’t been picked up were moved to nearby Fenside Public School.
Toronto police said the Donview Middle School is closed till further notice.