TRAPS set to discourage mountain bikers from off-road activities have been found hidden on isolated Forest tracks.
Biker Ian Ellis, of Lower Milkwall, near Coleford, has found wires set across paths, heavily spiked logs across trails and, most recently, wooden pallets with protruding nails hidden beneath pine needles placed on regular mountain bike runs.
"My fear is that someone is going to get seriously hurt or even killed," said Ian.
"It's a dangerous thing to do and could cause damage not just to mountain bikers but walkers, pets and horse riders."
Mr Ellis has found a number of traps in the Coleford area over recent weeks and believes they are being deliberately placed to discourage mountain bikers.
"I know not everyone likes mountain bikers in the Forest but on the routes I use I rarely see anyone, not even a walker.
"These traps are deadly. They have obviously been set deliberately. To string a wire across a path could cause a nasty crash and the pallets incident is frightening. It could easily cause a serious injury," he said.
For the Forestry Commission spokesperson Val Long said there had been previous incidents thought to relate to discouraging mountain bikers and that rangers checked out some areas on a weekly basis.
"It is obviously a very silly thing to do and contrary to Forest bylaws. We would have no hesitation in prosecuting anyone we found responsible," she said.
Mrs Long said that any incidents should be reported to the Forestry Commission.
"We would obviously be very discreet with any information we received," she said.
•Two years ago horse riders found a number of wires set at eye level across Forest rides and woodland tracks in the Pillowell and Yorkley areas.