UPDATE: Corn Belt Energy said all of its customers have power restored. Ameren also said power was restored by 2:20 p.m.
More than 9,000 Ameren customers were without power during the height of the outage.
UPDATE: About 80 customers remain without power as of 2:20 p.m., according to the Ameren Outage Center.
Thousands of customers in McLean County are currently without power after a transmission issue impacted multiple substations.
Corn Belt Energy said about 2,669 customers are without power in Bloomington, Normal, Hudson, McLean, Stanford, Shirley and Yuton after the issue at the Covell and Parkside substations.
As of 1:45 p.m., Ameren Illinois reports 4,910 customers without power in the Twin Cities region.
The origin of the power outage is currently unclear.