Millions in Spain, Portugal, and parts of France were hit by a massive power outage on Monday.

The blackout, which hit most of the Iberian Peninsula, was first reported around lunchtime local time.

In an X post, Spain’s grid operator, Red Eléctrica, said the causes of the blackout were being analyzed, and all resources are being dedicated to solving them.

As of around 7:30 p.m. local time, around one fifth of the peninsula’s power demand had been restored, Red Eléctrica posted on X.

Around 5 p.m. local time, the grid operator said electricity was returning to parts of the region, including Catalonia, Aragon, the Basque Country, Galicia, Asturias, Navarre, Castile and Leon, Extremadura, and Andalusia.

The operator estimated it would take six to 10 hours to restore the entire power, per the Spanish news agency EFE.

Eduardo Prieto, Red Eléctrica’s Director of Services for System Operations, described the incident to reporters as “absolutely exceptional and extraordinary.”

He said the blackout was likely caused by a “very strong oscillation in the electrical network” that caused Spain’s power system to “disconnect from the European system, and the collapse of the Iberian electricity network at 12:38 p.m.”

Rede Elétrica Nacional, the company in charge of transmitting and managing Portugal’s electricity, said it was working to restore the country’s electricity system, but noted in its statement the challenges of restoring a complete power outage.

Meanwhile, Spain’s National Cybersecurity Institute is investigating whether the blackout could have been caused by a cyberattack, according to local media reports.

The French regional newspaper L’Indépendant reported isolated power outages in southern French cities, including Perpignan.

The blackout halted operations at train stations, airports, businesses, and major buildings across affected areas.

In Barcelona, shoppers visited grocery stores in the dark

Customers faced with powerless food stands in Barcelona on Monday.

Customers faced with powerless food stands in Barcelona on Monday.

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Elevators went out, and Madrid emergency officials said firefighters had conducted 174 elevator rescues.

image of people helping lift man in wheelchair up stairs

With elevators not working, neighbors helped a man in a wheelchair up the stairs in Tarragona, Spain.

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Diners ate by candlelight at a restaurant in Burgos, Spain

image of diners eating by candlelight

A restaurant in Spain brought out candles and small lights for customers.

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The metro system in Spain’s capital Madrid was shut down and evacuated after the outage began

A metro station in Madrid in the dark during a widespread power outage in Spain on Monday.

A metro station in Madrid in the dark during a widespread power outage in Spain on Monday.

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Play was halted at the Madrid Open, one of the highlights of the clay court tennis season

The empty tennis court on day seven of the Mutua Madrid Open tennis game on Monday.

The empty tennis court on day seven of the Mutua Madrid Open tennis tournament on Monday.

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With little prospect of any more play, fans were sent away from the venue in Manzanares Park

Fans walked through the dark gangways during a general power blackout at the Mutua Madrid Open tennis game in Madrid on Monday.

Fans walked through the dark gangways during a general power blackout at the Mutua Madrid Open tennis game in Madrid on Monday.

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Fans streamed out of the exits into sunny, 70 degrees Fahrenheit weather

Fans walked through the dark gangways during a general power blackout at the Mutua Madrid Open tennis game in Madrid on Monday.

Fans walked through the dark gangways during a general power blackout at the Mutua Madrid Open tennis game in Madrid on Monday.

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Commuters waited in the shade after a Madrid train station closed

People wait outside a Madrid train station after its closure on Monday.

People wait outside a Madrid train station after its closure on Monday.

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People gathered in the street after leaving metro stations in the Portuguese capital, Lisbon

People out on the street after exiting a Lisbon metro station on Monday

People at a bus stop on the street after exiting a Lisbon metro station on Monday.

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Some in Lisbon also queued at ATMs to withdraw cash

People queued for the ATM in downtown Lisbon on Monday.

People queued for the ATM in downtown Lisbon on Monday.

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Trains were brought to a standstill, with passengers stranded near Cordoba, Spain

Passengers stand next to a stopped high-speed train near Cordoba on Monday.

Passengers sit near a railway embankment after their train stopped during the mass power cut in Spain.

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Substantial traffic jams were seen in Madrid

Vehicles queued on the M30 ring road in Madrid on Monday.

Vehicles queued on the M30 ring road in Madrid on Monday.

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