A power cut across swathes of England and Wales left almost a million people without electricity as traffic lights were knocked out, trains came to a standstill and aircraft were grounded during rush hour.
Passengers described “apocalyptic” scenes after the outage hit shortly before 5pm on Friday as people prepared to head home for the weekend.
Commuters were left using their phones as torches to find their way out of underground stations and airports, while British Transport Police officers were called in to assist station staff and crowds.
London Kings Cross station was closed to avoid overcrowding and passengers were also unable to travel from nearby St Pancras. Transport for London drafted in police officers in to manage busy junctions.
The National Grid Electricity System Operator later said issues with two generators were to blame for blackouts across London and the southeast, midlands, southwest, northeast and northwest.
A spokeswoman for UK Power Networks, which covers London, the southeast and east of England, said about 300,000 customers were hit by the power cut, while Western Power Distribution said about 500,000 people were affected in the midlands, southwest and Wales.
At least 110,000 Northern Powergrid customers in Yorkshire and the northeast also lost power, while at least 26,000 people were without electricity in the northwest, Electricity North West said.
Many people reported that the outage lasted just a few minutes, but there was a knock-on effect for rail and road commuters as delays continued into the evening.
One commuter described the scene at Clapham Junction in southwest London as “something out of an apocalyptic film”.
Harriet Jackson, 26, said she realised that “nothing was open and there was hardly any phone signal” when she emerged from Clapham Junction station at about 5pm.
She added: “All the traffic lights were down, but there were no police present, which meant it was dangerous to cross – cars weren’t stopping either. It was like witnessing something out of an apocalyptic film.
“No one knew what was going on and, given it’s a Friday afternoon, it’s the last thing you want to encounter.”
Newcastle Airport was also plunged into darkness when the power cut out for about 15 minutes, according to one traveller.
Scott McKenzie, 31, from Cardiff, said: “It was a bit worrying to start – more so because various alarms were going off and staff clearly didn’t quite know what was going on either.
“Some of the spaces in the airport have little daylight – we were literally plunged into darkness and people were using their phones as torches to see and get around.”
A back-up generator failed at Ipswich Hospital after the power cut, a spokeswoman said. The generator which was supposed to supply power to outpatient areas of the hospital did not work as expected.
"There were some issues with regard to our outpatient areas and the generator that provides cover (to them)," said the spokeswoman for East Suffolk and North Essex NHS Foundation Trust.
She said other generators "kicked in as was required" and "patients were kept safe and cared for throughout".
The problems lasted about 15 minutes before power was fully restored, she added.
Problems with power were first detected late on Friday afternoon, when UK Power Networks, who control power lines for London and the southeast, and Western Power Distribution in midlands, the southwest and Wales, both confirmed widespread outages.
UK Power Networks tweeted: “We’re aware of a power cut affecting large parts of London and South East. We believe this is due to a failure on National Grid’s network, which is affecting our customers.”
Western Power Distribution shared a similar message, and said they were in the process of restoring power to customers.
Thousands of people were also left disappointed after severe weather caused weekend events to be cancelled and disrupted across England.
High-profile music festivals such as Boardmasters and smaller events, including a kite festival, were called off after the Met Office issued weather warnings for rain, wind and thunderstorms across the country.
Press Association contributed to this report.
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