Trains ground to a halt and traffic lights were knocked out after a failure in the UK’s National Grid system left a large area of London and South East England without power, creating transport mayhem during Friday rush hour.

UK Power Networks, which controls the power lines for the British capital and the South East, confirmed the outage shortly after 5pm on Friday. The blackout was caused by “issues with two power generators” on the National Grid’s network.

We're aware of a power cut affecting a large area of London and South East. We believe this is due to a failure to National Grid's network, which is affecting our customers. We may not be able to answer individual tweets at this time. Please keep an eye on our feed for updates. — UK Power Networks (@UKPowerNetworks) August 9, 2019

Scenes of traffic apocalypse

The blackout struck at rush-hour, leaving those heading home from work stranded on trains, in chaotic traffic jams, or on the underground.

Service on the London Underground’s Victoria Line was suspended, and trains in and out of London have been hit with delays and cancelations.

Video footage shared on social media showed a throng of passengers walking through a darkened Clapham Junction station, while staff at Vauxhall Station turned commuters away and back onto the street.

Scenes at Clapham junction, commuters using phone lights in the tunnels. Also I just got trapped on the train as the doors stopped working. pic.twitter.com/wJjBAmoiOd — Ais Green (@AislingJane_) August 9, 2019

Chaos on the Victoria Line. The line is down and Vauxhall Station is shut. Power cuts in London :man-facepalming::man-shrugging: pic.twitter.com/FaVc62cm3l — Turkish Football (@Turkish_Futbol1) August 9, 2019

UK National Rail warned commuters that, due to the severity of the power outage, disruptions to train operations will continue on Saturday.

Thameslink said that its trains have been affected “to the point where they require a technician to restart them.”

Police officers could be seen boarding a stationary train in one clip.

Traffic lights were also affected and Transport for London (TFL) urged motorists to exercise caution on the roads.

Commuters and Londoners have been sharing stories of getting stuck in the train – or, for the luckier few, getting a free round of drinks in a blacked-out pub.

Power cut affecting Peckham. All traffic lights through town are out. It’s pretty chaotic. Hope @TfL@HighwaysSEAST? @lb_southwark@UKPowerNetworks are looking into this. Very precarious during rush hour, particularly at junctions where pedestrians are trying to cross as well. — Ledbury Action Group (@LedburyAction) August 9, 2019

it out, but they had the pull the emergency cord too. Now, we're finally moving again. I am keeping my fingers crossed! — MissBroom (@MissLCBroom) August 9, 2019

Power cut struck the pub just before we could pay. FREE. PINT. IN. LONDON. KLAXON. pic.twitter.com/PJwUgsiSHK — Michael Potts (@MichaelPottsRT) August 9, 2019

Up to ‘one million’ affected

UK Power Networks originally said the outage affected around 300,000 customers in London and South East England.

Similar outages were also reported in the Midlands, South West, and Wales, where 500,000 people were left without electricity, according to Western Power Distribution.

Northern Powergrid has said 110,000 of its clients were cut from the grid.

The Independent estimated the total number of customers affected at around one million.

After around two hours, the UK Power Networks said that “supplies had been restored,” but some people on Twitter kept complaining that they remained without electricity.

Outside the capital, an Ipswich hospital said it remained without power for about half an hour, but the medics managed to keep all of its patients safe. The Newcastle Metro also reported delays due to the power outage.

The blackout comes alongside miserable weather in London. Forecasters at the Met Office have issued a yellow weather warning, predicting strong winds and heavy rain overnight.

lovely weather and power cut here in London pic.twitter.com/pMhYKkgcDj — David Wyllie (@journodave) August 9, 2019

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