CHEERS erupted across Spain and Portugal on Monday night as electricity finally flickered back to life following a colossal blackout that plunged the Iberian peninsula into darkness.

The major outage brought two nations to a grinding halt — grounding flights, crippling public transport, knocking out hospitals, and shuttering stores from Lisbon to Barcelona.

The cause of the massive blackout, which began around 10.33am UK time, remains unclear.

Spain’s Interior Ministry declared a national emergency and deployed 30,000 police to maintain order as both governments held emergency cabinet meetings.

“This is something that has never happened before,” said Spanish Prime Minister Pedro Sanchez.

About 61% of Spain’s power was restored by Monday night, with electricity returning first to the Basque Country, Barcelona, and parts of Madrid.

In Portugal, grid operator REN confirmed 85 out of 89 substations were back online, including the capital Lisbon.

On the streets, people celebrated. Some cooked meals by candlelight, others flocked to plazas in impromptu gatherings, and supermarket shelves were stripped bare as residents rushed to stock up.

But what caused both countries to plunge into darkness is still unknown.

“There could be a thousand and one causes, it’s premature to assess the cause,” said Joao Conceicao, a board member of Portugal’s grid operator REN.

He suggested, however, the blackout may have begun with a “very large oscillation in electrical voltage, first in the Spanish system, which then spread to the Portuguese system”.

Spain’s grid operator REE pointed to a connection failure with France.

“The extent of the loss of power was beyond what European systems are designed to handle and caused a disconnection of the Spanish and French grids, which in turn led to the collapse of the Spanish electric system,” said REE’s Eduardo Prieto.

Pedro Sanchez revealed Spain lost 15GW of electricity in just five seconds – equivalent to 60% of the country’s demand.

“Technicians were working to figure out why that sudden drop occurred,” he said.

Despite swirling rumours of sabotage, Portuguese PM Luis Montenegro said there was “no indication” of a cyberattack.

Still, Sanchez confirmed he had spoken to NATO Secretary General Mark Rutte as a precaution.

BLACKOUT CHAOS

The fallout was swift and widespread.

Trains were cancelled, metros shut down, and traffic lights across both countries went dark.

In Madrid, residents took to the streets in reflective vests to direct traffic, and some were trapped in stalled metro cars and elevators.

Hospitals in Madrid and Catalonia suspended all routine operations but kept emergency rooms running on backup generators.

Several oil refineries shut down, while big retailers like IKEA and Lidl closed their doors.

Sanchez later said around 35,000 train passengers had been rescued, with 11 trains still stuck in remote areas.

Play at the Madrid Open tennis tournament was also suspended.

Online, Portugal’s internet traffic plunged 90% and Spain’s dropped 80%, according to Cloudflare Radar.

The Bank of Spain assured the public that electronic banking was still functioning “adequately” on backup systems.

While the lights are slowly coming back on, the full cause and cost of the outage remain under investigation.

Prieto warned it could take “several hours” for systems to fully stabilise.

BRITS IN DARKNESS

Brits abroad have had their holidays severely disrupted by the outages, and can’t even enjoy a pint to calm them down amidst the panic.

Melanie Halsall was 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.

Unlike holidaymakers in Benidorm it seems, she and her pals say they have “beer and biscuits” to live off during the carnage.

Melanie 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.

“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.”

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