Environmental health officers found a homeless person taking refuge at the site of a shut grocey shop - inside a fridge.
"Vile" TSK Cash and Carry, in Rayners Lane, was previously closed after kids' sweets were on sale "smothered" in rat poo.
An industrial size fridge was left in the back yard of the premises, surrounded by rubbish.
And it was in this fridge the homeless person was found living, Harrow Council has said.
A council spokesman said: "A street cleaner reported someone was living there. They'd obviously been going there at night for a roof over their head.
"Our environmental health officers went to investigate and found clothing and evidence of fresh faecal matter and foodstuffs."
The council will now liaise with a charity, as part of a homelessness intervention scheme, to find the homeless person a warmer, safer place to stay.
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