Hedge with brambles completely blocking the footpath

I am aware that this has been reported before BUT this hedge is now dangerous. There is no room to walk on the footpath and the brambles are hanging down to ground level. We are aware of one person being scratched by them. We have written twice to the residents of the property asking them to deal with the hedge but we have received no response. We are receiving complaints on a daily basis. We ask that this matter is addressed as a matter of urgency.