Underground explosion takes out power in Audubon Circle area

Update, 9:15 p.m. NStar reports more than 2,500 customers in Boston and Brookline have no power.

An NStar transformer in an underground vault along Beacon Street self-immolated shortly before 8 p.m., plunging many of the blocks around into darkness. Power in both Boston and Brookline was affected; fire officials refrained from exclaiming "oy, the vault!" but they were probably thinking it.

The outage extended to the Park Drive area, where firefighters responded to 15 Park Dr. around 8:20 p.m. to rescue somebody stuck in an elevator.