Power returned to much of Argentina and its neighbors Paraguay and Uruguay, following a massive blackout that left tens of millions of people in the countries in the dark on Sunday, but Argentine President Mauricio Macri said the cause of the "unprecedented" outage was still unclear.
Argentina's grid "collapsed" around 7 am (1100 GMT), leaving the entire country without power, Argentina's Energy Secretariat said. The outage also cut electricity to much of neighboring Uruguay and swaths of Paraguay, and shut down YPF SA's La Plata refinery, Argentina's largest such facility.
At around 7:00 pm (2200 GMT), Argentina's Energy Ministry Gustavo Lopetegui said services had been restored to 77 percent of customers in the country. There are still outages in multiple provinces, while Tierra del Fuego, in the country's extreme south, was spared because it is not part of the national system.
Bars and shops close their doors during the massive energy blackout in Argentina, June 16, 2019. /VCG Photo
In neighboring Uruguay, the state power company UTE said power had returned to at least 88 percent of the country.
The cut also affected Paraguay, which reported short, localized losses of power.
Argentine energy secretary, Gustavo Lopetegui, told reporters earlier in the day that the blackout started with a failure in the country's "interconnection system," known as SADI, but said the root cause of the outage remained unknown and that results of a full investigation would not be available within 10 to 15 days.
"There was a failure in the system, the kind that happens regularly in Argentina and other countries," said Lopetegui, adding that "a chain of events that took place later ... caused a total disruption."
Traffic lights stopped working in the massive blackout in Buenos Aires, Argentina, June 16, 2019. /VCG Photo
"This case is unprecedented and will be deeply investigated," Macri said on social media.
It was the first time a power cut had affected the entirety of both Argentina, with a population of more than 44 million, and Uruguay, which has 3.4 million inhabitants.
The blackout comes amid a deepening economic crisis in Argentina that has plunged nearly a third of the country into poverty, pushed interest rates skyward and sent the peso tumbling against the dollar, prompting mass protests throughout the country.
(With inputs from Reuters and AFP)