Council officers believe up to 15 people have been living in a three-bedroom house in Kingsbury which was raided over the weekend.
A shed in the garden of the property in Whitsby Gardens, is also thought to have been turned into a makeshift home.
The shocking discovery comes less than a month after 31 tenants were found living in a four-bedroom house in Napier Road, Wembley.
The raid is part of a council crackdown on landlords who dangerously cram as many tenants as possible into their properties to maximise their rental income.
In the Kingsbury case the council was given a tip-off about the property which was found to have failed to meet the most basic fire rules potentially putting the tenants’ lives at risk.
Since last year all landlords of Homes in Multiple Occupation (MHO) in Brent must be licensed.
To gain a licence the property must meet a certain standard which includes fire, health and safety regulations.
Cllr Harbi Farah, Brent Council’s lead member for housing, said: “Overcrowded, unsafe properties like this are a danger to the entire community. The landlord had squeezed in as many beds as he could while disregarding basic fire safety principles.
“The vast majority of landlords and lettings agents in Brent are honest and law abiding, but we take a zero tolerance approach to the minority who think they can treat their tenants like this.
“Our licensing scheme ensures that landlords maintain their rental properties to an acceptable standard. Failure to license a rental property could result in an unlimited fine and a criminal record.”
Last month Rehan Sheikh of Manor Drive, Wembley, was jailed for four months for illegally evicting tenants from his unlicensed HMO.
He has appealed the sentence and is out on bail pending a hearing date.
In March, married couple Gharmesh and Gita Khatri were fined £20,000 for renting out an unlicensed rundown HMO in Forty Lane, Wembley.
To find out more about the borough’s licensing scheme visit brent.gov.uk/prslicensing.
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