SAN FRANCISCO — A massive power outage Friday shut down much of San Francisco, with local authorities estimating that 90,000 consumers – roughly 1 in 10 residents – were left with without electricity.

Earlier in the day, an outage also hit New York, where subway riders found their commutes temporarily halted.

In an early assessment, authorities found no indication the outages were coordinated or related. Officials suspect aging infrastructure is likely to blame. A fire was reported at one area substation, but officials have not said whether that precipitated the outage, according to a San Francisco Chronicle report.

 

Pacific Gas & Electric officials said crews were investigating the cause of San Francisco's massive outage, and were aiming to "restore power safety and as quickly as possible."

Shortly before noon, PG&E tweeted it had restored power to 10,000 customers and said crews were working "safely & quickly as possible to restore more."

The blackout affected businesses, schools and tourism. Large office buildings in the city's Financial District, not far from the fabled Ferry Building, began emptying out not long after the outage hit around 9 a.m. Schools around the city dismissed students, while cable cars stopped shuttling visitors up and down the city's steep streets.

A major commuter station in the city's Bay Area Rapid Transit network, the Montgomery Street BART hub, went dark as travelers sought alternative means of transportation ranging from ride hailing cars to shuttles organized by the city.

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