Residents in downtown Halifax near Shirley, Cherry and Cedar streets could hear two loud booms, like cannons, before they lost power around 9:40 p.m. Friday.
Sirens followed as emergency vehicles rushed to the site.
Several eye witnesses say they saw bright flashes. Then sparks shot out of what appeared to be a transformer, followed by the smell of something burning.
Witnesses did not say there was a significant fire.
Signs point to a blown power transformer, but Nova Scotia Power has yet to confirm the cause of the outage.
One crewman was on the scene around 10:30 p.m.
As of 9:45, Nova Scotia Power estimated 115 customers were in the dark.
The utility estimates power should be back by midnight.
