The Police aren’t interested? That’s curious, as we have a similar neighbour – nothing for months and then he explodes!
I rang the Police during the last incident, and they were very proactive.
If this has happened more than once, then he can be charged under the Protection from Harassment Act 1997
http://www.legislation.gov.uk/ukpga/1997/40/section/4
I would call the Police again,quoting the Protection from Harassment Act.