RAPID CITY, S.D. (AP) - Officials say the causes of two large grass fires over the weekend that sent smoke over Rapid City are under investigation.
Fire Lt. Jim Bussell says the fires are believed to have started by humans, but whether it was accidental or intentional remains under investigation.
Firefighters on Sunday evening responded to a fire in the same area of a wildfire Saturday night.
Bussell said Monday both fires burned about 3½ acres. He says firefighters responding to Sunday's fire conducted a "burn out" in which additional brush was set on fire within the containment area to improve aesthetics, among other things.
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