A cannabis factory in Rhondda led police to further factories in Cardiff and Newport on Sunday (19 July).
Officers forced entry to a house on East Road in Tylorstown after neighbours reported suspicious activity and a distinctive smell coming from the property.
Bedrooms in the end of terrace house were being used to grow and dry approximately 100 plants at the address.
It was parking permit found in a vehicle which then led officers to Moira Street, Cardiff, where further plants were discovered.
A small number of plants were also located at an address in the Newport area.
Four men and one woman have been arrested and are currently in police custody.
Detective Sergeant Lia Jones, said: “Cannabis growing is a lucrative business and the money ends up in the hands of organised criminals.
“But, with the public’s help we can close them down quickly.”
Anybody who suspects cannabis growing should contact 101 immediately or they can dial 999 in an emergency.