A 25-year-old man has been left with 'extensive lacerations' across his neck after cycling into a rope strung between two trees on a popular throughway in Thetford, Norfolk.
The incident happened in the woods on Edinburgh Way on Monday, 24 August.
Police were also made aware that wood containing nails had been placed at head height down the alleyways from Edinburgh Way and Durham Way.
Police are urging bikers and cyclists to be extra careful.
Anyone with information should contact PC Nik Harris on 101 quoting crime reference: 36/60081/20.