450 customers in Financial District lost power

In San Francisco, 450 Financial District customers lost power during a 20 minute blackout on Friday night.

April 23, 2011 12:47:02 AM PDT
In San Francisco, 450 Financial District customers lost power during a 20 minute blackout on Friday night.

PG&E says it's not sure what caused the outage, but something apparently happened in a vault at the corner of Sacramento and Davis Streets.

Witnesses told ABC7 they heard an explosion, but PG&E hasn't confirmed that.

The utility did say the manhole cover was not displaced.