Hello my name is ***** ***** I will help you.
Just to be clear, no one knows where they are coming from?
Ah I see, that makes it difficult. Your only option is under the prevention of damage by pests act 1949.
2Duties of local authorities.
(1)It shall be the duty of every local authority to take such steps as may be necessary to secure so far as practicable that their district is kept free from rats and mice, and in particular—
(a)from time to time to carry out such inspections as may be necessary for the purpose aforesaid;
(b)to destroy rats and mice on land of which they are the occupier and otherwise to keep such land so far as practicable free from rats and mice;
(c)to enforce the duties of owners and occupiers of land under the following provisions of this Part of this Act, and to carry out such operations as are authorised by those provisions.
You should write and ask them to discharge their obligations. If they refuse then you should make a formal written complaint to the Chief Officer. That office will investigate the matter and report back to you.
if that does not work your final option is to complain to the Local Government Ombudsman. They offer a free, independent service and can examine your complaint at: www.lgo.org.uk
But follow the above steps, it should resolve your issue
Can I clarify anything for you about this today please?
All the best.