Sadiq Khan's creaking £19billion Elizabeth line suffered severe delays and cancellations yet again today - after a hellish night for commuters trapped in the dark for four hours who compared it to London in the Blitz.
Two people were injured when thousands of passengers including James Blunt and Rachel Riley were stuck on packed trains in the evening rush hour without power.
Groups - some of whom had already missed flights home for Christmas from Heathrow - were forced to smash their way out and walk down freezing tracks in the dark after being trapped amid the chaos following damage to overhead cables.
Mikey Worrall posted footage of passengers in the dark and said they were opening up the doors to get onto the line, adding: 'The Mayor of London needs to sort it out.'
He said the rush hour service lurched to a stop before a multiple-hour wait in semi-darkness as the driver drip-fed what little information they had to passengers.
Eventually, the battery backup running the heating and lighting ran out, and those on board were left in darkness for another hour and a half until the evacuation came.
Describing his 'surreal evening', Mr Worrall added: 'Every day, it's a different excuse. It seems to me they opened this whole thing without actually being fit for purpose.
'If they knew there were infrastructure issues that they needed to work on, why didn't they work on those before? They opened the line and it doesn't work. It (goes down) multiple times a week, and it's incredibly frustrating.'
And there were more problems this morning amid huge questions for Mr Khan about the Elizabeth line's reliability after MailOnline revealed it had the sharpest increase in cancellations of any UK rail route in the latest quarter compared to last year.
Great Western Railway and Heathrow Express, which operate trains on the same routes through West London, were also running reduced services this morning.
On the Elizabeth line today, there were severe delays between Abbey Wood and Whitechapel as well as London Paddington and Heathrow - with disruption expected until at least 3pm due to the overhead wires problems in the Ladbroke Grove area.
Transport for London (TfL) said tickets were being accepted on Underground trains, buses and other mainline rail routes including Thameslink and Southeastern - but the Central line was then also hit by delays this morning due to a 'shortage of trains'.
GWR issued an alert to passengers saying 'do not travel' between Paddington and Reading until further notice, adding that services between Oxford or Didcot Parkway and Paddington will terminate or start back from Reading. Long distance services 'will run where possible' but likely faced 'short notice cancellations and alterations'.
Countdown's Rachel Riley was one of those stuck on board the train from 6pm last night, and posted a selfie of her and other passengers smiling on board, captioned: 'Nearly four hours after we got on, we're getting off the Elizabeth line, woohoo!'.
Seemingly also among those trapped was singer James Blunt, who said: 'Been stuck somewhere outside Paddington for close to 4 hours now. Out of peanuts and wine.'
People climb down onto the tracks after being stranded on an Elizabeth Line train in semi-darkness for more than three hours
Passengers start making the long walk back in the cold after their ordeal stuck on board the the train
The power failure meant the lights went off inside trains while the heating was also unable to work leaving passengers freezing cold
Passengers on board one train on the Elizabeth Line have been stuck for more than two hours waiting to be rescued
A video showed passengers sitting in a blacked out carriage of the 1837 Paddington service with their faces being lit up by the glow from their mobile phones
No trains were running between Paddington and Heathrow during the evening rush hour, with National Rail and Heathrow Express services also disrupted, leaving passengers stranded on rail strike day.
Those on trains were made to wait for more than three hours until police started evacuating carriages, with some passengers resorting to forcing the doors open and 'self evacuating' before emergency services had arrived.
Footage obtained by MailOnline shows passengers carrying heavy suitcases along the tracks in the pitch dark after they disembarked the train and headed back towards Paddington.
Elderly people, children and even the chief executive of Network Rail were among those stuck on carriages where temperatures plummeted when the heating stopped working due to the power failure.
A mother carrying a newborn said a woman fainted on her train while another passenger claimed people were forced to use the tracks, and even their seats, as toilets. Two people were treated for minor injuries and discharged at the scene.
The chaos meant some passengers missed their flights they had booked to see loved ones for Christmas while workers were unable to get to their shifts as people took to social media to vent their fury at Transport for London for providing no updates.
After breaking free from trains, people were left to wait in huge queues for taxis in order to get home, with national rail strikes leaving many with no other transport options.
The Elizabeth Line has been plagued by delays since it fully opened this year, and it was revealed in August that it has seen more cancellations than any other railway line.
National rail, Elizabeth line and Heathrow Express services were all disrupted by the issue, Transport for London said. Transport Secretary Mark Harper said on X: 'Aware of a serious incident involving overhead wires outside Paddington, with a number of trains stationary on the tracks.'
There was further chaos at Paddington with hundreds of stranded passengers packed inside the station waiting for taxis home.
TfL apologised for the disruption with engineers said to be working through the night to assess the damage.
Passengers have been urged by Network Rail to check before they travel in the morning.
A TfL spokesperson said: 'We're sorry that the damage caused to Network Rail's overhead power lines by another rail operator's train has caused significant disruption to our Elizabeth line customers as well as all train operators out of London Paddington.
'We're working together with response teams across partners to recover trains and get everyone home as quickly as we can.
'Network Rail are working urgently to repair the power lines and we'd encourage all customers to check before they travel over the next few days while they do this.'
Paramedics and a Hazardous Response Team from the London Ambulance Service were sent to the Paddington area where two people were treated for minor injuries.
Pictures posted on X, formerly known as Twitter, showed passengers standing on packed trains which had been stuck on the tracks for more than an hour.
A distressed mother said her daughter suffers with debilitating anxiety and had been on board her train for three hours.
She vented her frustration at Transport for London (TfL) for failing to update her.
'She [my daughter] suffers with debilitating anxiety and has poor comprehension, not to mention bladder issues meaning she needs the loo and is freezing cold,' she told MailOnline.
'She won't ask for help. No information is being given. TfL keep cutting me off at the point of answering and all I want is information that I can simplify for her.'
One passenger boarded a train at Acton at 6.41pm which stopped within five minutes and was still waiting to be rescued more than two hours later.
Another passenger dramatically described it as 'like the Fall of Saigon' and the Elizabeth Line 'has failed again just when passengers needed it most'.
Dr Bamo Nouri was one of those stuck and said the line had 'almost completely blacked out'.
Dr Nouri wrote on X: '#Elizabeth line has almost completely blacked out with a fully loaded set of carriages and many standing. No real or substantial updates, no sense of urgency - been sat for almost an hour!'
Transport for London expects delays to last for the rest of the day.
One frustrated commuter said: 'The Elizabeth Line has failed again just when passengers needed it most. At Paddington there were old folk, people with babies with absolutely no way of getting home.
'It was like the Fall of Saigon, except in that case some lucky people actually managed to get on the helicopter.'
One eyewitness claimed on X a train ahead had hit some overhead lines, although this is yet to be confirmed by TfL.
While another said a train driver had to shout at passengers trying to get off the train.
A video showed passengers sitting in a blacked out carriage of the 1837 Paddington service with their faces being lit up by the glow from their mobile phones.
Passengers left in the dark on board a train as one passenger huddles over their suitcase while others are forced to stand
An overhead power failure to to damage wires has left people stranded on packed carriages on the Elizabeth Line tonight
Voiceover artist Danny Cowan, who has appeared on Channel 4 and Netflix, said some passengers were trying to get off the train
The darkened carriage on a tube train on the Elizabeth Line where people had been standing for 90 minutes
Office of Rail and Road data on the cancellations score by operator from July to September 2023 and the percentage point (pp) change compared with the same period last year
Danny Cowan, a voiceover artist who has appeared on Channel 4 and Netflix, was making his way to his agent's Christmas party when the train came to sudden halt more than an hour ago.
He wrote on X the heating had gone off and he was so cold he could barely think.
He said: 'Hey any fear you might get this FREEZING COLD (no heating) Elizabeth Line train moving that's been stuck outside Acton Town for over an hour now?
'The driver has already had to shout at passengers who are trying to get off. Some information would be nice.'
Emma Bentley has been stuck between Paddington and Acton for 90 minutes.
She said: 'The carriages have now lost power, and it seems we may be walking home…'
Another stranded passenger was having his patience tested and wrote: 'We have no power, so can't move! I need a pee - mind over matter!'
The disruption is expected to last until the end of the day with current delays of 60 minutes.
No trains are calling at stations between Paddington and London Heathrow and Reading while the final Heathrow Express has also been cancelled.
In August, the Office of Rail and Road figures revealed that there had been more cancellations on the Elizabeth line than any other railway line, and the new line has gained a reputation for disruption among commuters.
One in six of its services was delayed or cancelled over the summer and in October it suffered six separate issues in just over 24 hours.
A London Ambulance Service spokesperson told MailOnline: 'We were called at 7.38pm yesterday to reports of a large number of passengers delayed on trains between Paddington and Ladbroke Grove, west London.
'We sent a number of resources to the scene including an ambulance crew, a paramedic in a fast response car, an incident response officer and members of our Hazardous Area Response Team.
'We treated two patients for minor injuries and discharged them at the scene.'
MailOnline has contacted Transport for London for comment.
Are YOU stuck on an Elizabeth Line train? email matt.strudwick@mailonline.co.uk