LOUISVILLE, Ky. — At least 11 employees were taken to hospitals and residents were urged to shelter in place on Tuesday after an explosion at a Louisville, Kentucky, business.

News outlets reported that neighbors heard what sounded like an explosion coming from a business that manufactures ingredients for soft drinks. Overhead news video footage showed an industrial building with a large hole in its roof.

“The cause at this point of the explosion is unknown,” said Louisville Mayor Craig Greenberg. No one died in the explosion, he added.

Greenburg said officials spoke to employees inside the plant. “They have initially conveyed that everything was normal activity when the explosion occurred,” he said.

The Louisville Fire Department said in a post on the social platform X that multiple agencies were responding to a “large-scale incident.”

Louisville Metro Emergency Services urged people within a mile of the business to shelter in place.