Police in North Yorkshire have given landlords a list of danger signs following a surge in cannabis farms.

Rental properties in the county – and across the UK – are typically favoured by drug growers because of absentee landlords.

A spokesperson for North Yorkshire Police says: “Cannabis farms are sophisticated set-ups used by organised crime gangs to produce several crops of the drug over time.

“Cannabis production is extremely harmful to communities, and often used to fund criminal gangs involved in human trafficking, sexual exploitation and the distribution of other drugs including cocaine and heroin.

“Furthermore, the electricity supply may have been tampered with (to by-pass the meter), creating a high risk of fire – which could spread to neighbouring properties.

“Residential and commercial premises could be used as cannabis farms, so today we’re issuing a warning to landlords to be vigilant around your properties.”

Here are some of the possible signs to watch out for:

– Poor or no references from a previous letting agent or landlord;

– Offering to pay several months in advance;

– Preference to pay rent in cash without reasonable cause;

– Wanting to keep utility bills in a landlord’s name;

– Asking for complete privacy, requesting no periodic inspections or preventing the inspection of the property when given reasonable notice;

– Changing locks to keep landlords and agents away from a property.

Landlords suspicious about tenants and cannabis farms can call their local police or Crimestoppers anonymously on 0800 555 111.