Millions of people and entire cities descended into darkness as a massive, unprecedented power failure kept Argentina and Uruguay in the dark on Sunday morning, the same day as provincial elections were to be held in parts of Argentina. Parts of Brazil and Paraguay also were affected, according to the BBC.

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 #APAGON pic.twitter.com/aTFYbU2cDL — Nicolás (@NicRigl) June 16, 2019

According to Buenos Aires-based electricity supplier company Edesur, Argentina suffered a “nationwide” blackout, which also affected neighboring Uruguay, said the company's spokesperson, Alejandra Martinez, adding that "Something like this has never happened before."

Absolutamente todo sin luz!!! Increíble pic.twitter.com/cY3gNrq3uO — Lucas (@lucas_m_rod) June 16, 2019

The company had earlier explained that the massive power outage happened due to a failure in the electrical interconnection system. The blackout itself started at 7:07am local time on Sunday, according to Argentinian officials.

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 #SinLuz pic.twitter.com/tvyxuMjTts — AFP news agency (@AFP) June 16, 2019

In a subsequent tweet, Edesur said that power is gradually being restored, starting with an initial 34,000 customers. Electricity in Buenos Aires and the greater capital area is also coming back online. “The process of normalization, which will require several hours, is beginning,” according to Edesur.

Nuestro Centro de Control inició las demandas de normalización y lentamente comienza a restaurarse el servicio de energía eléctrica a la red. Ingresamos los primeros 34.000 clientes. — Edesur Argentina (@OficialEdesur) June 16, 2019

Argentina’s Civil Protection Minister Daniel Russo estimated that it will take between six and eight hours to fully restore power in the country of over 44 million.

Argentina, South America’s second-largest economy, shrank 2.5% last year, and its economic contraction - the worst since 2014 when the nation defaulted on its debt - has only accelerated since then, prompting question if the IMF's largest ever bailout of a sovereign nation will also be its biggest disaster.

According to Argentina’s Civil Protection Minister Daniel Russo, it would take between six and eight hours to fully restore power in the country of over 44 million.