Hanover Police say its careless smoking which led to a fire last Thursday.
Police were called to the fire on 10th Street which was extinguished by a passerby before emergency services could arrive.
With the help of the Hanover Fire Department and video surveillance, the fire was determined to have started accidentally by a cigarette.
Police Chief Christopher Knoll says the incident serves a reminder of the dangers of careless smoking and the responsibility everyone has to ensure every flame is properly extinguished.