Video from TWITTER/SPECIALKAMIK
A blocked toilet sent raw sewage pouring through a block of flats in Wembley lived in by key workers.
A stomach-churning video showed rooms and communal areas at the Lexington Building in north west London soaked in brown liquid.
Towels, bedding and a basin were stuffed around a toilet to try to limit the damage, but sewage seeped across the floor and into neighbouring rooms.
The council, which owns the building, said it was making "urgent repairs" and helping any affected residents.
In one video clip a resident wearing flip flops could be seen treading carefully through the soggy mess
"The two affected flats and the communal areas will be deep cleaned, and we’ve found alternative accommodation for the tenant who has been directly affected in the meantime," Brent Council said.
"As soon as we were alerted to the problem yesterday, we dispatched an engineer to make urgent repairs and to remove the blockage.
"Officers were on-site talking to residents all day and delivered letters to flats with advice about the communal areas that were affected.
"When our engineers left yesterday, it appeared the issues had been resolved," the council added.
But the problems didn't stop there as another leak sprung up in the bathroom of a different flat.
The council added: "We dispatched emergency engineers as soon as possible, and officers have been at the building speaking to residents all morning. We’re treating this matter very seriously, and are on hand to help anyone at Lexington who is affected."
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