91.(1) In the case of a public nuisance the ¹[Attorney General], or two or more persons having obtained the consent in writing of the ²[Attorney General], may institute a suit, though no special damage has been caused, for a declaration and injunction or for such other relief as may be appropriate to the circumstances of the case. (2) Nothing in this section shall be deemed to limit or otherwise affect any right of suit which may exist independently of its provisions.