At least it wasn't in the kitchen
Give him train ticket back to Croydon
Environmental management is the first step. Eradicate all possible food sources, such as feeding the birds, compost bin and food waste.
Speak to neighbours to ask them to stop feeding the birds, foxes and any other animals.
If problem persists I recommend placing poison inside external bait stations, available in most hardware stores.
If they are nesting nearby, it is most probably under a shed.
It might not be a good idea to involve the council. Our neighbours had rats near a compost heap, the council put poison out and the rats, like all animals, then searched for somewhere quiet and dark in which to die. They managed to get under the floorboards and the stench made the house virtually uninhabitable for four weeks. They should be killed instantly or trapped and then dealt with.
Give the blighter a damn good kick in the testicles.