Power is steadily returning to two southwestern US states and Mexico, following a massive blackout which affected more than five million people.
Services to Arizona were restored early on Friday, while parts of California and the Mexican state Baja California have also since been reconnected.
The BBC reports the outage was triggered after a piece of equipment was switched off at a substation in Arizona on Thursday.
Investigations are continuing into how the power cut spread so widely.
The blackout caused transport chaos, with traffic lights being knocked out and trains and flights being cancelled.
Two nuclear reactors in California were forced to shut down.
