Clark County firefighters responded to a condominium complex located at 4827 Longshot Dr. near Tropicana Avenue and Boulder Highway on Sunday morning.
Upon arrival, three units were affected by smoke.
Of the three units, two were unoccupied and one had five adult occupants who were sleeping.
Firefighters knocked on their door to wake up the occupants and escorted them to safety.
No one was injured.
Clark County fire investigators determined the cause of the fire to be an improperly discarded cigarette.
The damage is estimated at $40,000.
The Red Cross is assisting the occupants.
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