Police are urging residents to stay alert after a series of cannabis cultivation sites were uncovered in properties believed to be unoccupied across Renfrewshire.
Officers have carried out search warrants at 20 addresses since the start of the year, with many of the properties identified as vacant rental accommodation.
At each location, cannabis plants were found growing at various stages of maturity.
Police say they are also increasingly discovering electricity meters being illegally bypassed to power the operations, creating serious safety risks.
In total, 17 people have been arrested and more than 10,000 cannabis plants seized, with the estimated street value of the most mature plants exceeding £5 million.
Detective Inspector Gordon Smith said: “This work has been ongoing in Paisley, Renfrew, Gourock and Greenock over the past three months and we are seeing an increasing number of properties being used which the public and neighbours may think are unoccupied.
“Those involved in drug supply may come to the address for a short period of time – perhaps even 20 or 30 minutes – at different times across the day.
“We are seeing sophisticated instances of the electricity meters being bypassed within these properties. This does not only present a fire risk to the property itself, but neighbours and adjacent properties, especially within common closes or flats.”
A spokesperson for Scottish Power Energy Networks warned of the dangers of tampering with electricity supplies.
They said: “Electricity theft and tampering with power supplies are extremely dangerous crimes that put lives at risk. Interfering with electrical equipment can cause fires, severe electric shock, and widespread power outages that impact entire communities.
“Our engineers regularly see the aftermath of dangerous, makeshift wiring, and it’s only through swift action from fire crews that more serious injuries are avoided. We work closely with police to identify and respond to incidents of tampering, and we urge anyone who suspects illegal activity to report it immediately.
“The consequences of electricity theft can be devastating — no one should risk their life, or the safety of others, for the sake of bypassing a meter.”
Group Commander Rod Anderson of the Scottish Fire and Rescue Service added: “One of the most common causes of fires in the home is overloaded circuits and malfunctioning appliances.
“With marijuana farms using substantial amounts of electricity, there is a real fire risk.
“These types of fires can spread rapidly, igniting nearby materials, which makes them difficult to extinguish quickly. When these burn, they can produce a variety of toxic fumes and gases.
“Bypassing electrical meters not only causes a significant risk to a property, but also to neighbours and nearby buildings.
“The Scottish Fire and Rescue Service will continue working alongside Police Scotland to identify and reduce any such fire risks.”
DI Smith added: “We are committed to disrupting the supply of drugs. People may view this as not a harmful substance, however in production cases, this often masks other forms of serious and organised criminality.
“I’d urge anyone with concerns of drug crime in their area, or has information that can assist our enquiries, to report this to us so that we can investigate.”
Information can be passed to Police Scotland via 101, or anonymously to Crimestoppers on 0800 555 111.