Power returned to much of Argentina and two neighboring countries following a massive blackout that left tens of millions 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 a.m. (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.
