Entire cities descended into darkness as a massive, first-of-its-kind blackout swept across Argentina and Uruguay over the weekend. While power has been restored in Argentina, it has yet to fully return in Uruguay.

Argentina suffered a “nationwide” blackout, which also affected neighboring Uruguay, Alejandra Martinez, a spokesperson for the Buenos Aires-based electricity supplier company Edesur, told local media. “Something like this has never happened before,” she said.

VIDEO: 🇺🇾 Residents of Uruguay's capital #Montevideo wake up to no electricity after a massive electricity cut left Argentina, Uruguay and some parts of neighbouring countries in the dark, according to Uruguayan and Argentine electricity companies #apagon#SinLuzpic.twitter.com/tvyxuMjTts — AFP news agency (@AFP) June 16, 2019

The blackout itself, which affected as many as 44 million people, started at 7:07am local time on Sunday. It took the company around 10 hours to restore services to households after 5:30pm. The company had earlier explained that the massive power outage occurred due to a failure in the electrical interconnection system.

Ahora en Boedo se ve como CABA está sin luz, aún no hay información oficial de @OficialEdesur . Estoy esperando al medicio a domicilio por mi hija de 2 años con 39 de fiebre. Vivo en un 9° piso. #SINLUZ#APAGONpic.twitter.com/aTFYbU2cDL — Nicolás (@NicRigl) June 16, 2019

Gigantesco apagón en la #Argentina: la Ciudad, la Provincia de Buenos Aires y Santa Fe se quedaron a oscuras https://t.co/VOGlJZS3rOpic.twitter.com/w4ToTkonAD#Apagón#SinLuz#SinAgua — ⭕️ Mario Morínigo Moray (@mmmoray) June 16, 2019

Neighboring Uruguay, with a population of roughly four million, also suffered a power outage at the same time. The utility company, UTE, had managed to restore 98.5 percent of its service "from zero" by 6:30pm. The firm said that works would continue “until dawn.”

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Paraguay, Brazil and Chine also reported localized losses of power throughout the day.

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