CCTV investigations in London Road, Kingston found a mound of fat the size of a bus had reduced the 70 x 48cm sewer to just 5% of its normal capacity.
Thames Water has begun repairs to 20 metres of the damaged pipe and work is expected to take up to six weeks to complete.
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A man has died and two others have been injured in a stabbing outside Parsons Green Tube station.
Dany Cotton says referring to 'firemen' reinforces the stereotype that only men want to work in the fire service.
His heart completely stopped and one of his teammates performed CPR until paramedics arrived.