By Adam Jourdan and Eliana Raszewski

BUENOS AIRES — Argentina and Uruguay were scrambling to restore power to millions of people after a massive power failure hit the Argentine grid early on Sunday, Argentina's Energy Secretariat said.

Energy company Edesur Argentina said it had restored power for 75,000 clients in the greater Buenos Aires area by 10:52 a.m. local time (1352 GMT).

Total recovery was estimated to take a few hours, according to the Energy Secretariat and Edesur.

The massive outage left Buenos Aires dark early this morning, hobbling public transportation, cutting off water supply and crippling phone and internet communications across the city.

Several Argentine provinces were forced to temporarily delay local elections.

The cause of the outage was still unclear as of late morning, but Argentina´s energy agency said in a statement it had begun an investigation.

A spokesman for Brazil's power system operator (ONS) said the outage had not impacted the regional neighbor to the north. — Reuters