At least nine people were seriously injured on Thursday after a suspected gas explosion inside a beauty salon wrecked two adjacent stores in the Chicago suburb of Illinois.

Dan Young, Deputy Fire Chief said one person was treated at the scene for the blast and other eight were taken to a hospital although none had life-threatening injuries.

Fire crews at the scene maintained the fire and extinguished all the flames by mid-afternoon.

The blast occurred at around lunchtime in the business district, 40 miles north of Chicago, shattering windows and collapsing the roof of the plaza which housed a cell phone shop, a tuxedo and a hair salon.

Young said they are certain the explosion was caused by a natural gas explosion.

Information from the hospital indicated that two of the eight people admitted with blast injuries, were in serious conditions, with injuries ranging from smoke inhalation, bumps to bruises.

I was taking orders at Leno Submarine Shop a block away from the shopping plaza when the blast hit, said Candi Rixie, who was near the scene of the explosion.

We felt like an earthquake, like somebody had hit the building with a car, added Rixie.

The spokeswoman for People's Gas said a crew was on the scene but hadn't been able to get close enough to identify the cause of the explosion