Power returning in Spain and Portugal after unprecedented blackout that left tens of millions without electricity

• Some power has returned to parts of Spain and Portugal
• Spain's Interior Ministry has declared a state of emergency following the power outage
• Multiple airlines report disruptions to services
• Lisbon metro completely stopped
• Most of Spain’s traffic signalling goes offline sparking chaos
• Madrid Metro evacuated
• People urged to only use phones when necessary

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The cause of the massive outage remains unknown, Spain's Prime Minister Pedro Sánchez said. He told reporters that no cause can be discredited at this point.

About half the electricity supply in Spain has now been restored, Sánchez said on Monday evening, adding that the rest of the grid should be running again by Tuesday.

It comes as supermarket shoppers appeared "visibly worried" as they queued on the streets of Barcelona, a Brit visitor has said, as some suggested the outage was "planned by hackers" - a claim that has since been dismissed by governments.

Long queues formed outside shops across Spain, with residents and tourists alike stockpiling goods including bottled water and canned food.

Officials have been trying to keep affected people calm, as Sánchez urged the public not to speculate about the cause of the outage and call emergency services only if absolutely necessary.

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Eduardo Prieto, the head of operations at Red Electrica - the operator of the Spanish electric grid - called the event "exceptional and extraordinary".

Power is expected to be restored sooner in Portugal, according to the country's prime minister Luis Montenegro.

Some citizens could be seen stockpiling essentials, with others lining the streets to take out cash from local banks.

Spain's Interior Ministry has declared a state of emergency. The emergency status will be applied to regions that request it, the ministry said.

While some areas have started to regain power, thousands of people continue to feel the impact of the outage, with homes and business without energy and public transport services cancelled.

Images from the affected regions show train stations closed, police officers directing traffic due to signalling problems and long queues at the supermarkets as people stock up on essentials.

Portugal's grid operator, REN (Rede Eletrica Nacional) claimed interruptions to the country's power supply were the result of a "fault in the Spanish electricity grid".

They said this was related to a "rare atmospheric phenomenon", namely "extreme temperature variations".

Red Electrica, which operates the national electricity grid in Spain, said on X the energy supply recovery is progressing.

They said: "There is already electricity supply in areas of Catalonia, Aragon, the Basque Country, Galicia, La Rioja, Asturias, Navarre, Castile and Leon, Extremadura and Andalusia."

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Public transport chaos

Barajas Airport in Madrid remains without power while the Valencia metro has suspended all services.

Spain's national rail operator, Renfe, said on X this evening no medium and long distance trains are expected to operate today.

Phone lines have also been affected. Spain's Prime Minister Pedro Sánchez asked the public to use phones "responsibly", urging people to only use phones for brief calls and necessary communication while the system is being fully re-established.

Madrid's mayor warned residents to stay put during the outage. Sharing a video on social media, José Luis Martínez-Almeida said: "I ask all residents of Madrid to keep their movements to an absolute minimum and, if at all possible, to remain where they are. We want to keep all roads clear."

He also urged residents to only call emergency services if it is "truly urgent", adding: "If emergency calls go unanswered, go to the police and the fire stations in person, where they will try to deal with all the emergencies which may present themselves."

There have also reports of outages in France and Germany. France's grid operator RTE issued a statement saying parts of the country briefly lost power.

Madrid open cancelled

Monday’s play at the Madrid Open has been cancelled due to the power outage.

Britain’s Jacob Fearnley was forced off court when play was initially suspended just after 12.30pm local time.

The third-round tie between Fearnley and Grigor Dimitrov had reached a critical stage, Fearnley breaking the 15th seed’s serve to stay in the match, when a loss of power in the local area affected scoreboards and the camera above the court.

A statement posted on the Madrid Open’s X account read: “For reasons beyond the control of the organisation and in order to guarantee general safety, the nationwide power-cut experienced in Spain on Monday April 28 has forced the cancellation of both the day and night sessions at the Mutua Madrid Open.”

Red Eléctrica, Spain's national grid operator, said it was working to restore power following a system failure across the entire peninsula.

"The causes are being analysed and all resources are being dedicated to resolving it," the operator explained.

Speaking at a press conference, CEO Eduardo Prieto said it could take "between six and 10 hours" to solve the issue.

The Spanish government has convened a crisis meeting due to outage, according to the El Pais paper.

"A crisis committee has been set up to manage the situation [in Spain]. At this stage there’s no evidence yet regarding the cause of the massive blackout," an official briefed on the situation said.

"A cyberattack has not been ruled out and investigations are ongoing."

In Portugal, a country of some 10.6 million people, the outage hit the capital, Lisbon, and surrounding areas, as well as northern and southern parts of the country.

Portuguese distributor E-Redes said the outage was due to "a problem with the European electricity system", according to Portuguese newspaper Expresso.

The company said it was compelled to cut power in specific areas to stabilise the network, according to Expresso.

Portugal's national electric company, REN, said a fire in the south-west of France may be the cause of the outage.

The fire damaged a high-voltage power line between Perpignan and eastern Narbonne.

'Eerie atmosphere' in supermarkets

Jack, who is on the west coast of Portugal, told LBC of there is "eerie atmosphere" in the shops.

He said: "We have lost power and lost water, most about an hour now. But we've found a nice little local supermarket.

"There's a group of nine of us, and we've stocked up on water and food. We're holding out for information because we haven't had any yet."

Power in the UK remains unaffected but the situation is being monitored closely, NESO (National Energy System Operator) said.

Craig Dyke, Director of System Operations, said: "Great Britain's electricity network continues to operate as normal, we are monitoring the situation closely and are liaising with our counterparts in neighbouring European countries to offer any assistance that may be required."