Several public and private travel guides, such as The Rough Guide to Jerusalem and the British government's travel advisory for Israel, warn against driving in Jerusalem on Shabbat, as residents of certain neighbourhoods may stone the car.
I know that driving on Shabbat is generally prohibited by the orthodox Judaism practised in these neighbourhoods. But what is the halachic or rabbinical basis, if any, for their stoning cars to enforce this prohibition? If there is such a basis, is it permitted to throw stones even at cars driven by gentiles (who are presumably the primary target audience of the above-mentioned travel guides)? Or must one first ascertain that the car is being driven by a Jew, and that the driving is not being done due to a life-threatening emergency?