An "unsafe and unsanitary" property rammed with bunkbeds was found to be home to 28 people following an early morning raid.
The four-bedroom, one-bathroom house in Mollison Way, Edgware, had a fly-tipped and rat-infested back yard, was in a dreadful state of disrepair and had no smoke detectors throughout.
Horrified enforcement officers from Harrow Council carried out the raid at the property following a complaint of overcrowding.
But they weren't expecting to find a family of five, including children, living in a tiny room, plus bunkbeds rammed in every available space, including the common room, and damp and dirt everywhere.
The majority of tenants were Romanian, mostly workers, and the family were suspected to be sub-letting, the council said.
During the raid, 17 people were found inside the property but on counting beds it was realised as many as 28 people lived there.
The landlord claims he knew nothing about it and assured the council he will get the property licensed and deal with the overcrowding.
Harrow Council's cabinet member for environment, Councillor Graham Henson, said: "Can you imagine being crammed into a house with more than twenty people?
"What a horrible way to live. And how the landlord did not know about this is shocking. It’s unsafe, unsanitary and exploits people who really want a decent place to live.
"As it’s the landlord’s responsibility to check on their property, we will be forcing him to make repairs, deal with the overcrowding and get it licenced or face a big fine.
"Our licensing scheme is there to ensure incidents like this don’t happen. We’ll continue to carry out raids and seek to prosecute anyone found flouting the rules and operating illegally."
The council says it is looking to take legal action as no such application has been recieved.
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