The power was flickering before it went out for about an hour in several parts of Iroquois County.
Ameren Illinois representative Stacey Stockton-Shangraw said the official outage began at 1:17 p.m., and it came back for good at 2:06 p.m.
“The cause is unknown,” she said.
Mike Wilson, a representative from Eastern Illini Electric Coop, said its customers also had the outage due to a transmission system.
“It was the same issue,” he said.
Crews patrolled the lines and did some switching to reroute power, she said.
The outage affected a little more than 2,000 Ameren customers and 1,200 EIEC customers, noting the areas of Watseka, Sheldon, Iroquois, Beaverville and Donovan.