What is this ferret-like mammal?

Hi,

This creature ran quickly in front of our camera last night at 3am.
The slab it is crossing in the still image is about 45cm x 45cm.
Judging by when it runs by the black planter, it looks like its back is about 25ish cm high.
We live in a rural location in the midlands about a third of a mile from a river.

Thanks