Calgary police have charged a teacher with sex offences involving a teenage boy.

The charges stem from an inappropriate relationship allegedly between a 30-year-old female teacher at Our Lady of the Assumption elementary school and a 16-year-old boy who previously attended classes there.

“We are shocked and saddened by this recent development,” read a letter sent by the school to parents on Friday.

The activity allegedly began when the boy was 15 and took place between August 2012 and November 2013.

“She was teaching at the same school,” said Staff Sgt. Kelly Campbell of the child abuse unit.

Campbell said she couldn’t specify whether the teacher and boy were in the same class, to protect the identity of the complainant.

The boy, now 16, attends high school elsewhere in the city.

Campbell said the allegations came to light last November, when a passerby called police about “inappropriate interaction” between two occupants of a vehicle parked on a northwest Calgary street.

At this time, police don’t believe there are any other victims involved in the case.

Police arrested a suspect on Thursday.

Jennifer Mason, 30, has been charged with sexual assault, sexual exploitation by a person in a position of trust, sexual interference and invitation to sexual touching.

Although the general age of consent for sexual activity is 16, the Criminal Code forbids sexual activity between minors under 18 and adults who hold a position of trust over them, such as teachers and coaches.

A Calgary Catholic School District spokeswoman said it immediately launched an internal investigation and re-assigned Mason to duties outside the school when police informed school officials of the allegations last November.

The board later suspended Mason following its parallel investigation into the allegations.

The School Act requires school boards to continue paying teachers under suspension.

Due to a citywide teachers’ convention, schools across the city were closed on Friday.

Catholic school spokeswoman Tania Younker said the district will provide counsellors for staff and students at the affected school when classes resume on Tuesday.

Mason is scheduled to appear in provincial court on Feb. 28.

jvanrassel@calgaryherald.com

Twitter: JasonvanRassel