Calgary firefighters responded to a number of fires involving power poles on Wednesday morning, leading to electrical outages in parts of western Calgary. (CBC)

A series of electrical pole fires caused brief power outages in parts of western Calgary early Wednesday morning.

Nearly 4,000 Enmax customers lost electricity for a few hours in West Springs, Patterson, Cougar Ridge, Coach Hill and Bowness, the power company said.

The fires are triggered by a common spring phenomenon called “tracking,” the fire department says.

A build-up of grime and dirt in the insulators — which are used to attach the electrical wires to the power poles — can spark a fire if they overheat in light rain, snow or fog.

Fire officials are reminding the public that pole fires and downed power lines can be extremely dangerous and people should never approach them or try to extinguish these fires.