A person who assembles with other persons in any public way or public place or in any open space or ground in the immediate neighbourhood of such public way or public place—
(a) for any idle, lewd, vicious, or disorderly purpose; or
(b) for a purpose other than in the regular performance or pursuit of any lawful occupation or purpose,
so as to cause the annoyance or obstruction of any passer-by or other user of such public way or public place or of any person residing in the neighbourhood thereof, and does not disperse or move away when required to do so by any police officer, or person residing in or near such public way or public place, or by any passer-by or other user of such public way or public place, is liable on summary conviction to a fine of $1,000.