CHATTANOOGA (WRCB) -- Chattanooga firefighters spent Monday afternoon battling a large fire at Mountain Creek Apartments on Mountain Creek Road that left several residents homeless.

Fire Department Spokesman Bruce Garner confirmed that two firefighters were treated for smoke inhalation.

They were both treated and released from Erlanger Medical Center.

Witnesses say all the residents and what appears to be all of their pets had been evacuated safely, but at least units of Building C appeared to be a total loss.

Garner says the fire has been ruled accidental, and says a cigarette is believed to be the cause.

He says approximately 40 residents were displaced by the fire.

The Chattanooga chapter of the American Red Cross responded to the scene to assist residents left without a place to stay.

Stay with WRCBtv.com for the latest on this developing story.