land dispute

[baz_05]

Hi My mother's naighbour has put up a fence & shed encrouching on her land, she only has her pension as income with little savings. He has damaged her property in doing so. I've tryed to speak to him but had the door slamed in my face by his wife. Any adice what I can do next as it's stressing my mother who is in her eighty's and live there over 50 years.
Thanks