That is incorrect.
You can only be held responsible for a fire if it is due to negligence on your part.
You do have a duty as a property owner to take all reasonable measures to guard against the outbreak of a fire.
If for example you were storing hazardous goods in a dangerous manner and they caught fire which spread to the adjoining property you would likely be considered liable.
A court case Nugent-v-Foley 2015 held this to be the case.
If on the other hand if you forgot that an electrical appliance was still on and it was the cause of a fire this would (most likely) be considered accidental and you would not be held responsible for damage to a neighbouring property