More than 5,000 Ameren customers in Lincoln and surrounding areas were without power Friday.

Problems at two substations caused a fault on a transmission line that provides electricity to the city. Ameren spokeswoman Marcelyn Love says it’s unclear why the substations failed.

Love says Ameren is restoring power to the area about 1,000 customers at a time so as not to overwhelm the system. She anticipates everyone will be back up by 6:00 Friday night.