Nine people from the UK have been cautioned by police for riding their motorbikes in restricted off-road areas.
Police penalised them on Friday after they were caught in the Central Hills - which is an Area of Special Scientific Interest.
Officers say they could have caused damage to the physical landscape of the forestry and "immeasurable distress" to wildlife including nesting Hen Harriers which are protected.
They say incidents like this are measured on their "individual circumstances" with other penalties available including prosecution, large fines and penalty points on riders' licences.
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