A minor has been charged after allegedly making online threats against a high school and the safety of students and staff.

Calgary police learned about the threat through a social media site Nov. 20 that launched a "complex investigation involving a number of units," according to a release.

A 15-year-old male student has been charged with possession of a weapon, threats and extortion. 

Police have not named the high school and the accused cannot be named under the Youth Criminal Justice Act.