Cahokia Assistant Fire Chief Stephen Robbins said the call came in at 12:30 p.m. and the first firefighters found heavy smoke and lots of heat.
"They made it about 10 feet in the door before they had to back out due to safety reasons," Robbins said.
The coin laundry was scheduled to close April 30. It was closed when the call came in Wednesday and no one was inside, Robbins said.
He said it is too soon to say whether it might be an accident or an arson, but the Office of the State Fire Marshal is being called to investigate. As a result of the cleaning chemicals that could be housed in the business, he said St. Clair County's hazardous materials team was being brought in.
Firefighters were also trying to control the water coming off the fire, to keep any hazardous materials out of the storm sewers.
Twelve departments with 40 to 50 firefighters were working the fire. Robbins said the 80-degree day and low water pressure from the old hydrants in the area were hampering their efforts.
Three aerial trucks were spraying water on the fire, but tankers were brought in to supplement the hydrants.