(Bloomberg) -- A huge power failure cut off electricity in Argentina and Uruguay on Sunday morning, according to media reports and a regional utility.

Parts of Brazil and Paraguay also were affected, the BBC reported. The outage hit on a day of provincial elections in parts of Argentina.

A “massive failure in the electrical interconnection system” has left “all of Argentina and Uruguay without power,” Edesur Argentina, a power company serving more than 2.5 million customers, said on Twitter.

Argentina’s government is assessing what caused the outage and how to fix it, according to an Energy Ministry statement cited by the Clarin newspaper, which said the grid collapsed at 7:07 a.m. local time.

Work is under way to restore power, though the outage may last hours, according to the statement.

Argentina, South America’s second-largest economy, shrank 2.5% last year, the worst since 2014 when the nation defaulted on its debt.

(Updates with Argentine government statement in fourth paragraph.)

To contact the reporter on this story: Tony Czuczka in New York at aczuczka@bloomberg.net

To contact the editors responsible for this story: James Ludden at jludden@bloomberg.net, Matthew G. Miller

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