Three people are charged with allegedly selling cocaine and heroin from a St. Catharines residence.
Niagara Regional Police say mobile transactions were also taking place throughout the city.
Police have been watching the home on Greenlaw Place since January and on Monday they moved in to make some arrests.
Charged with Possession of Cocaine and Heroin for the purpose of trafficking and possession of proceeds of Crime is 53 year old Derek Coenjarts , 47 year old Caroline DeJong and 34 year old Issac McAndrews.
All three remain in police custody pending a bail hearing in St. Catharines court on today.