Capt. Steve Haywood of the Ottawa Fire Department said the train's tanker cars were shipping ethanol for Decatur-based corn processor Archer Daniels Midland, and possibly other materials and chemicals. At least six tanker cars are burning, Haywood said.
Witnesses have reported hearing explosions, and the glow from the fire could be seen from miles away.
"There's a lot of fire and big flames," said Amanda Knight, who told the Chicago Sun-Times that the train derailed about 500 feet from her home.
Knight said she heard several explosions coming from the accident scene.
"It sounds like a jet coming over the town. That's all I can compare it to," she said.
There's no word yet on any injuries. Authorities say the town's evacuees are being taken to Princeton High School.
The train had 126 cars and more than 60 carried ethanol, said Aaron Whittington, a dispatcher for Oglesby's police and fire departments. The railroad company planned to bring another engine to the scene to move some of the cars and open up some of the railroad crossings so fire trucks could pass, he said.
The train was operated by Iowa Interstate Railroad. A dispatcher with the railroad said company officials were headed to the scene Friday.
Tiskilwa is a village of about 800 people located about 100 miles west of Chicago.