Part of a street in Birmingham city centre were cordoned off after an underground fire reached above the surface in big flashes of flame.
West Midlands Police said the flames seen on New Street shortly before 17:00 GMT were caused by an electrical fault below.
West Midlands Fire Service said it was liaising with power suppliers to isolate the problem electrics.
There are no reports of injuries, police said.
Shoppers and workers who were about to make their way home shared images of the scene, where tram travel was disrupted.
The fire service said it would tackle the blaze from within a service hatch, once the electrics were isolated by engineers.
A Western Power Distribution spokesman said 103 properties had been affected by a power outage as a result of a fault with a junction box.
He added that power had been restored to 60 properties by 19:00 GMT, and the remaining properties should have their power restored by 01:30 on Saturday.
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