Approximately 700,000 users across Greater Buenos Aires suffered a lengthy power cut on Tuesday as temperatures hit sweltering highs, soaring above 40 degrees Celsius.
Electricity distributors Edenor and Edesur said major power outages had taken place as demand for energy spiked, with both blaming technical failures for the fault.
Homes, shops, businesses and offices were affected by outages "in high-voltage lines" and "machines at Central Puerto," the National Electricity Regulatory Body (ENRE) said in a report.
"These failures caused an outage of approximately 1,800 MW. An estimated 700,000 users are affected by the event. Central Puerto is currently carrying out start-up work in order to begin normalising the supply," it added, revealing that demand had reached 9,800 MW at around 1pm.
The outages came at the worst possible time, with mid-afternoon temperatures on Tuesday rising to 41.5 degrees Celsius, according to the National Meteorological Service.
Authorities in Buenos Aires City said Tuesday that the heatwave had delivered a high of 41.1 degrees Celsius at 4.05pm local time – the second-highest reading in the capital since 1906.
Official weather forecasts anticipate similar highs on Thursday and Friday, with cooler temperatures expected to arrive on Sunday.
Almost 15 million people live or work in the Buenos Aires Metropolitan Area. Power was gradually restored across the region, though many were left to suffer for hours, with some users reporting outages lasting longer than six hours.
Predictably, the outrage prompted a political row, with former president Mauricio Macri taking to social networks to criticise the government. The Juntos por el Cambio leader posted a black square in reference to the power cut, while calling on his followers to share it on their own accounts to express their anger.
Opposition lawmakers followed suit, blaming the ruling coalition for a "lack of investment" and failure to rise the price of utilities.
National deputy María Eugenia Vidal declared on Twitter that: "We are living the consequences of the patches and the improvisation of Kirchnerism that in the end all Argentines end up paying for."
Responding to the criticism, Government Spokesperson Gabriela Cerruti accused Macri of hypocrisy, saying the country is "still" waiting for "explanations" for a similar outage on Father's Day in 2019, which she claimed left "millions without power" for "almost the entire day.