This is the rule of strict liability or liability without fault.
The principle in this rule is that a person who for his own purpose brings on his land and collects and keeps there anything likely to do mischief if it escapes does so at his peril and is prima facie answerable for all the damage which is the natural consequence of its escape.
This principle was formulated in Rylands V. Fletcher where an employer was held liable for the negligence of an independent contractor.
For this rule to apply, certain conditions are necessary:
o Non-natural user of land
o Bringing, collecting and keeping things.
o Things must be capable of causing mischief if they escape.
o Things must have escaped.
o Interference with the plaintiffs use of his land.