Karla Homolka leaves her family home in St. Catharines, Ont., in this July 6, 1993 file photo. Homolka served 12 years for the rapes and murders of teenage girls, including her younger sister.

AP Photo/CP, Frank Gunn

A convicted serial killer has been doing volunteer work at a private elementary school in Montreal, according to local reports. 

According to the Canadian Press, Karla Homolka occassionally volunteered at Greaves Adventist Academy, which is operated by Seventh-Day Adventist Church. The school says Homolka supervised a field trip and brought her dog into a classroom to play with the students, but she was not a regular volunteer and wasn’t allowed to be alone with the children. 

Homolka was released from prison in 2005 after serving a 12-year sentence for murdering and raping two school girls, Kristen French and Leslie Mahaffy, according to the Montreal Gazette. Her ex-husband, Paul Bernardo, is currently serving a life sentence in prison for his role in the case.  

The church says it won’t allow anyone with a criminal record to volunteer on school grounds. 

The Canadian Press reports Homolka is no longer allowed to volunteer at the school. 

A lawyer for the French and Mahaffy families told told The Canadian Press that the news of Homolka’s volunteer work is a “kick in the gut” to the victims’ families. 

© 2017 CBS Interactive Inc. All Rights Reserved.