neighbour hit our child, troubles us in different ways

Dear Sir/Madam, We stay in a an apartment in bangalore. our neighbours used to abuse us for small things like garbage kept outside our house. We used to keep the dustbin outside our door and this lady used to ring our bell and abuse us for no fault of ours. Our neighbour(wife of neighbour) hit our child 10 years back when he was only 3 years and denied. His daughters were studying in the same school as our child and they used to pinch/push him in bus in our absence. When we used to get angry they used to record this. We changed our childs school to be safe. They still harass us in lift, in the apartment when we are alone. His daughters spiltted water outside our house and we scolded them and complained to building office they installed a cctv camera just outside the entrance which they are using to threaten us. Their daughters call us on our intercom and give bad words. They even make fun of us in the apartment in front of their friends(not in front of their cctv so that their