Two Quebec high school students are facing several charges after a “courageous” tip from one of their parents foiled an alleged murder plot, police say.

The male suspects, aged 14 and 16, were arrested on Wednesday. Both were charged with three counts of conspiracy to commit murder and criminal harassment and one charge of attempting to administer a date rape drug.

Police said the intended victims were three boys and one girl, all fellow students at Ecole Polyvalente Hyacinthe-Delorme, in St-Hyacinthe, Que. The suspects were allegedly planning to kill the three boys and sexually assault the girl.

Surete du Quebec spokesperson Audrey-Anne Bilodeau said the arrests came after one suspect’s mother found threatening messages and details of the alleged plot on one of her son's social media accounts.

“A search was held in the school and an investigation was able to demonstrate that the young people were about to execute their plan,” Bilodeau said, adding that a knife was found in one of the boys' lockers.

The suspects will remain in police custody until a court hearing, which will take place on either Monday afternoon or Tuesday.

With files from CTV Montreal