I was chased across Stanley Park, heading to Lime Street, in 1970, by combined Liverpool and Everton for my DMs.
Fortunately I could run a bit back then.
They used to brick the MUFC 'specials' on the way to and from the ground, too.
A shit hole then - still is , IMHO.
Easy does it, Ed - my mum was born there!
The rivalry between Liverpool and Manchester goes back to the 19c when the Manchester Ship Canal was built and loads of jobs disappeared in Liverpool.