According to BlurtIt:
   It has been found that about 90% of forest fires are due to human factors. Smokers may start a forest fire by carelessly dropping lighted matches and cigarettes in a forest. Campers and picnickers or tourists may also start a fire by throwing lighted items on the ground or into the bushes. Some times sparks from locomotives powered by coal or wood may also ignite dry grass or trees beside the railway line.


Wrong again,GfS.