A massive power outage in San Francisco caused a blackout Friday morning in neighborhoods across the city, from the Financial District to the Presidio, forcing the closure of businesses, a BART station, cable car service and a federal courthouse, officials said. A spokesman for Pacific Gas and Electric Co. said 95,000 customers lost power and that there had been a fire at a substation at Larkin and Eddy streets. It wasn’t immediately clear whether the fire caused the outage, which swept through the city shortly after 9 a.m., or was ignited as a result of the outage. As of 11...