Emporia Fire Marshal Reason Bradford says the cause of Thursday's fire at 603 East 11th is currently undetermined.
The mattress in question was destroyed. Firefighters contained the fire to a bottom-floor apartment.
Firefighters initially called the blaze suspicious, but Bradford isn't making that statement at this time. Bradford says the investigation is considered open for the time being.
One person suffered minor injuries but refused treatment. One person was also detained on scene. Emporia Police have not said whether the person detained was the one hurt.
If you have information about the fire, call Bradford at 343-4239 or Emporia Police at 343-4200.