Being English, I can see both sides of this sorry tale.
Being nosy, I'd love to read the other person's account of the incident.
My guess is that it goes along the lines of:
"I have spent months asking politely that the neighbours children stop destroying my neat, tidy front garden with their football game - and asking them in particular not to touch my brand new car. Their parents have been no help at all, even though they know there is a problem, and I eventually snapped and called the Police. The Policeman sympathised with my plight and said that he had advised the parents to prevent their children from causing any further annoyance."
I suspect that the truth lies between the account given here by the parents, and my fictitious account from the neighbour.
As to what happens next ... who knows? Compromise would be nice (and very English), but confrontation seems more likely.
The winners, if there are any, will be the ones who can produce some evidence if/when the (probably quite irritated) Police return. I'd get a video camera and use it ... a sad situation though.
dave