CHICAGO (CBS) — A tent set up at the Autism Speaks Walk event at Soldier Field caught fire.

It happened just before noon. Firefighters say a propane tank exploded causing the tent to catch fire.

A 60-year-old worker inside the tent suffered smoke inhalation and was taken to Northwestern Hospital in good condition.

There were no injuries to walk participants. The event continued as planned. It’s unclear what caused the tank to explode.

“My first reaction was hoping that everyone was going to safe,” said Keith McCormick, the Executive Director of Autism Speaks. “And thank goodness everybody was.”