SPAIN has declared a national emergency after a massive blackout hit it and neighbour Portugal cutting all power.
Airports and hospitals shut down and trains screeched to a halt across the peninsula - with officials blaming a "rare atmospheric phenomenon".
Panic-stricken shoppers across Spain and even Portugal are clearing supermarket shelves and leaving grocery stores empty amid chaos.
Have you been affected by the outages in Europe? Email sayan.bose@the-sun.co.uk
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Alarming pictures posted on social media show bare supermarket shelves after panic-shopping swept across the affected regions.
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Footage shows people forming huge queues outside grocery stores and ATMs to stockpile essential items amid fears the mayhem could last for days.
And there are fears that thugs will exploit the chaos and darkness to loot shops after nightfall.
One shopper Alfonso Romay wrote on X: “It’s incredible, the collective paranoia. The power goes out for five hours, and look at the supermarket.
“The water jugs in the image lasted less than one minute.”
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Roads in Spain, Portugal and parts of France were left snarled up with traffic as lights and signals went blank - with emergency officers drafted in to tackle the bedlam.
Some hospitals cancelled all surgeries for Monday amid fears for patient safety in the region's most severe blackout for years.
Spain's train service came to a complete stop, leaving huge crowds stranded at stations, and Madrid's underground network was evacuated.
But Spanish PM Pedro Sanchez confirmed that power has been restored in some areas of the north and south of Spain.
Air traffic was slashed to "half capacity" as flights were cancelled from a number of airports - with Lisbon cancelling all arrivals for hours.
And a major tennis tournament, the Madrid Open, had to be suspended, with Brit Jacob Fearnley's match interrupted by a huge "bang".
Data from Spain's electricity grid shows an enormous drop-off in supply over a matter of seconds, just after midday.
Michael Dearson-Jones from Ibiza told The Sun: "The mobile networks are down in Ibiza since late afternoon. Power is on, but limited access to the internet.
"No calls, texts or mobile internet. Landline internet is working, but intermittently."
Jessica Ratcliffe from the Canary Islands - a popular Brit tourist hotspot - told The Sun: "An alert has been issued to residents in the Canary Islands that basic food supply shipments from the mainland will be impacted, causing panic buying there too.
Rampant panic buying in Canary Islands. Alerts have been issued saying we could face severe food shortage
Jessica Ratcliffe
"There has also been a failure in the internet, mobile phones, data phones and ATMs.
"Businesses and freelancers on the islands warn of restrictions on card payment and problems withdrawing cash."
Portugal's national grid operator, REN, said it believes a "rare atmospheric event" could be behind the outage.
It said that extreme temperature variations in Spain possibly led to surges in current and then system failures, in a process called "induced atmospheric variation".
They added that it could take up to a week to fully solve the issue given its complexity.
Red Eléctrica, Spain's national grid operator, has not given an explanation for the blackout but vowed that "all resources are being dedicated" to solving the issue.
As of 3pm, it said power had been restored to several electricity stations in the north, south and east.
Spain's prime minister Pedro Sánchez’s rushed to the operator's HQ to monitor the response himself.
It's like being in a Netflix drama.
Nuno Feist
Many had raised fears that a "Russian cyberattack" is behind the chaos, following previous similar plots against Europe.
There was speculation that Putin's meddling was involved in the Heathrow fire last month, which depleted the whole airport of power for a day.
Juanma Moreno, president of the Andalusian regional government, had said a cyber attack is the most likely cause of the disruption - and claimed that everything pointed towards a deliberate plot.
He added that hospitals would only be able to rely on their generators for 24 hours.
An outage of this scale is extremely rare and has caused mayhem for millions, including Brits on their holidays.
Melanie Halsall is on the last day of a padel trip with six pals to Vale de Lobo, southern Portugal, and can't get back into the hotel room.
She told The Sun: "We were on a walk when suddenly everything went out.
"We can't buy anything because the card machines aren't working - not even water or ice cream. But we have got beer and biscuits so we're surviving on that.
What is induced atmospheric variation?
INDUCED atmospheric variation refers to changes in the Earth's atmosphere in response to external factors.
The changes can be in temperature, pressure, or other atmospheric conditions.
It can be driven by a range of thing including natural events, such as solar activity and volcanic eruptions, or human activity.
Sudden changes in these factors cause a reaction from the Earth's atmosphere.
Portugal's electricity operator, REN, said that in this case the problem was caused by extreme temperature variation in Spain.
This led to "anomalous oscillations" in very high-powered electricity lines, which prevented systems from synchronising properly.
In turn, that spread disturbances across the interconnected European network, REN added.
"Everyone is saying it's a Russian cyber attack. It's quite worrying. We're all mums and need to contact our families, but our phones are about to run out and we can't charge them."
Portuguese musician Nuno Feist, 53, from Lisbon, told The Sun: "It's like the dark ages here, we don't have access to news, and we can't turn on the TV.
"It's like being in the Netflix drama Zero Day. We believe it is a cyber attack."
Brit Lottie Feist, 23, studying translation at uni in Lisbon, Portugal, told The Sun: “There is no electricity, nothing is working. The roads are absolute carnage as no traffic lights are working.
"All the power is down. It's terrifying, people will be stuck in elevators, and everything has completely shut down.
"Some people are saying it’s a cyberattack and are pointing the finger at Russia.
"We have no idea what has caused it at this stage - and it appears the authorities don't seem to have any clue either.”
The European Commission said on Monday it was "in contact" with Spanish and Portuguese authorities "to understand the underlying causes".
A spokesperson said: "The commission will keep monitoring the situation and make sure that there is smooth information exchange amongst all relevant parties."
Antonio Costa, who heads the European Council of EU member states and a former Portuguese premier, is also in contact with the Spanish and Portuguese leaders, an EU official said.
In Spain, officials urged drivers to stay off the roads, and the Valencia metro announced it had suspended its entire service.
Thousands of traffic lights are down in Barcelona, with drivers negotiating complicated junctions without any help.
Healthcare workers in Madrid said they have been forced to prioritise the transfer of chronically ill patients on oxygen machines - some of whom cannot survive more than an hour without a supply.
Hospitals are having to rely on their emergency generators to keep people alive.
Huge queues grew at ATMs as debit card payments were down, so people rushed to get cash out.
Portuguese supermarkets closed for "safety reasons", and some gas stations were restricting their supply.
Civilians also got trapped in various spaces - including lifts at a Madrid station and the carriages of Lisbon Metro.
Holiday Headache
Brits on holiday in Spain and Portugal have had their plans derailed.
Ashley Brown, 38, of Newcastle, was planning to fly home this afternoon but her plans were cut short after all card payments were cut off.
The hair stylist, who is on holiday with a pal, told The Sun: “We were looking at getting the train back to the airport but there’s no way of paying.
“All payments are down. I can’t draw any money out. It’s an absolute nightmare. I’m meant to see clients in the morning and I can’t call to cancel.”
She added: “It’s things like this that really put it into perspective for you. I’ve got no way of paying for anything, and it’s really difficult to get something simple like a bottle of water.
It was absolutely surreal. It was likes a horror film.
John Stevenson
“My flight is gone and there’s no way I’m gonna be able to explain this, I can’t even call back home.”
A number of flights have departed from Barcelona airport, but the roads surrounding the travel hub are chock full of traffic.
The airport is believed to be running on emergency power supplies. But hundreds of Brits are struggling to get out of the city.
Publican John Stevenson, 53, is on holiday with his wife and two adult children after jetting out to Barcelona on Tuesday last week.
He said: “The first thing I noticed was I couldn’t get down from the fifth floor of my hotel, I thought it was just us to begin with.
“I went down to the supermarket and the whole place was in complete darkness, it was absolutely surreal. It was like a horror film.
“I was able to pay in cash, but at this point in a holiday I have just a little bit that I was looking to get rid of at the airport. If this went on for days it would be hell.
What does it mean for your flight?
THE Sun's Head of Travel Lisa Minot weighs in.
THE massive power outage across Spain and Portugal has thrown transport networks into chaos.
With Madrid’s international airport closed, flights are being delayed and could potentially be cancelled if the power cut goes on for a significant period.
While there is no compensation due to consumers for delays or cancellations as the chaos is outside of any airline’s control, they do have a duty of care.
If your flight is delayed by more than two hours, your airline should be providing you with food and drink - sometimes in the form of vouchers - as well as access to phone calls or emails.
If you are delayed overnight, accommodation and transport to and from the airport should also be provided.
With a sudden incident such as this, it may be necessary to pay for essentials but make sure you keep all receipts and keep any purchases reasonable.
If your flight is cancelled, your airline has to get you to your destination as quickly as possible - and by any means necessary, even if that means on a different airline’s flight.
However, practically in situations where thousands are impacted, it may be that you have to make your own arrangements - again, make sure your expenses are reasonable and will get you to your destination within a reasonable amount of time. Keep ALL receipts.
You are also entitled to a full refund but remember, if you choose this option, you are on your own and the airline is not responsible for getting you home.
If your travel insurance policy includes travel disruption cover then it may be possible to claim for disruption or losses incurred as a result of your trip being delayed or cancelled.
However, it’s worth noting that not all policies cover this as standard, and cover levels, conditions and exclusions can vary between providers, making it important to check with your insurer as your first port of call.
“I’ve got a hire car and will be driving to the airport later, but I’m nearly empty on fuel and I’ve not been able to fill up anywhere.
“It just goes to show you, everything can go from being fine, to be in potentially dangerous, completely out of the blue.”
The dad, of Southampton, Hants, added: “We are too reliant on technology. I’ve always told my kids this, and now I can see.
“I just hope nobody was hurt during this. It’s mayhem.”
Brit Wendy McNeil said: "Here in Tavira, Portugal, we have had no power since around 11.30am.
"The restaurants are trying to keep going with many cooking on gas, the shopping malls are empty as shops are closed, the town in general is very ghost like and it’s very strange."
Pius Bentgens, in Lisbon, told The Sun: "Suddenly the tram just came to a halt.
"We could tell something was off because the air conditioning stopped - it felt eerily quiet.
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"Then texts started coming in from a friend on the other side of the city that power was out there as well."
Another Brit, 29, of Northampton, said: “It’s been half price on ice cream. Aside from that it’s a mega ball-ache. There could be looting later.”