TORONTO -- A former youth group leader is facing 21 additional charges in connection with alleged sex-related offences that took place at churches and temporary Halloween stores across the Greater Toronto Area between 1997 and 2009.

Last month, police charged a 43-year-old man with three counts of sexual exploitation and three counts of sexual assault stemming from alleged incidents that took place between 1998 and 2003. The incidents, investigators said, involved three teenagers.

In a news release issued by Peel Regional Police on Thursday, investigators from the Special Victims Unit said they have since heard further allegations of offences that took place over the span of 12 years at churches and temporary Halloween stores in Brampton, Mississauga and Georgetown.

The suspect, identified by police as Mississauga resident Daryl Holliday, is now facing 21 additional charges, including sexual interference, invitation to sexual touching, sexual exploitation, sexual assault and making child pornography.

He is scheduled to appear in court on March 29.

Investigators say there may be additional victims and are encouraging anyone with information to contact the Special Victims Unit at 905-453-2121 ext. 3460 or reach out to Crime Stoppers anonymously.