Found this, maybe it will jog someone's memory. No lyrics found and I am out of time just now:

"Mr Fox was a folk-rock band formed in 1970 by Bob and Carolanne Pegg, to further their musical ideas, which were moving away from the traditional material that they had successfully employed to become a respected duo on the folk club circuit.

The final song is the macabre masterpiece,"Mr Fox", a haunting, gruemome tale of a strange man, his grisly deeds and even nastier end. Sung by Carolanne, with a superb undercurrent of menace provided by cello, organ, violin and bass, with an electric guitar crashing in at moments of high excitement. This song personifies the whole strange character of Mr Fox,the group."