Mechanism for the addition of chlorine to benzene to form hexachlorocyclohexane

I am familiar with electrophilic substitutions of benzene, with chlorine using a halogen carrier catalyst such as $\ce{AlCl3}$, to produce chlorobenzene, and I am aware of the mechanism.
But, apparently, one can get the addition of chlorine to benzene, where the delocalised structure is disrupted and hexachlorocyclohexane is formed.


I would like to know the mechanism for this addition reaction.


