Power has been fully restored in south Etobicoke after an outage left about 4,500 customers in the dark on Thursday morning.

Police say they were dispatched to the northeast corner of Fifteenth and Birmingham streets at around 9:15 a.m. after live power wires were seen sparking on the ground.

Toronto Hydro says it cannot confirm what caused the wires to fall but has determined that the transformer is fine.

The outage initially affected 4,500 customers in an area bounded by Lake Ontario to the south, the Gardiner Expressway to the north, Kipling Avenue to the west and Park Lawn Road to the east, however power was quickly restored to all but 100 customers.

Power was then restored to the remaining 100 customers by 1 p.m.