CALGARY -- After about five hours, power has been restored to thousands of residents in Brooks and area Saturday and crews are still determining what caused the outage.

FortisAlberta Inc., which provides services to half a million homes and businesses in Alberta, listed the outage on its website.

Data indicates that power was knocked out for 8,306 customers in Brooks, Alta. and the surrounding areas in Newell County at about 7 a.m.

Officials with AltaLink, the company that operates the system where the outage was detected, say their control centre was alerted to an issue at the Brooks substation.

"After performing an inspection, the crew identified damage on some of the equipment in the substation," said Amanda Sadleir, corporate communications manager with AltaLink. "The cause of the damage is unknown and continues to be investigated."

Following the discovery, Fortis managed to safely restore power through its distribution system while the substation repairs are underway.

All affected residents had their power restored shortly after noon.