California, Arizona and Mexico hit by blackout

A massive power outage overnight Thursday caused blackouts in California and Arizona, and in Mexico, and left an estimated five million people without electricity.

Agence France-Presse said emergency workers rescued several people from elevators and theme park rides, while California’s two nuclear units tripped offline automatically.

The blackouts knocked out traffic lights across the region, with San Diego the worst affected city. Authorities there also canceled all outbound flights.

In Los Angeles, trains were halted because of power cuts to lights and signaling.

By late Thursday evening, San Diego Gas & Electric (SDGE) it had restored power to 18,000 customers in Orange County.

An incident in the network between Arizona and California reportedly caused the outage, which comes amid sweltering temperatures.

Damon Gross, a spokesman for the Arizona power company, APS, said two failures were to blame for the power cut:

One is human failure and the other is a system failure. Both of those will be addressed.

SDGE posted a warning on Twitter urging customers to turn off air condition units, or risk triggering a second shutdown once electricity is restored:

Hot days in a row like we have had create lots of power flowing.

The Associated Press reported that the U.S.-Mexico border was “cloaked in darkness”. Police on both sides were deployed to prevent looting.