London: Major power failures hit large areas of the UK, affecting trains, airports and traffic lights.
UK Power Networks on Friday said on Twitter that large parts of London and the South East are without electricity.
"We believe this is due to a failure to National Grid's network, which is affecting our customers," said the UK Power Networks, which owns the power lines in London, the South East and East of England.
Meanwhile, Western Power Distribution (WMD) also tweeted: "We are currently experiencing a major incident on the national electricity infrastructure." It is the electricity distribution network operator for the Midlands, South West and Wales.
It later said: "90 percent of customers are now restored and we are working hard to restore the remaining customers as soon as possible."
Train services in and out of London, including Thameslink, Southern and Gatwick Express are facing delays and cancellations because of the disruption.
Network Rail said that trains across large parts of England were stopped after a "power surge on the National Grid" but its signaling system has now come back online.
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