Off-road bikers have been blamed for damaging an area of woodland in Sheffield.
South Yorkshire Police suspects that damage in Wickfield Plantation - a wooded area at the bottom of Coisley Hill, between Woodhouse and Intake - has been caused by off-road bikers creating a dirt track.
The force claims trees have been chopped down, fires have been started to clear the land and holes have been dug.
Police patrols have been stepped up in a bid to catch the culprits in the act.
A force spokesman said: "Wickfield Plantation is a wooded area at the bottom of Coisley Hill, which has paths and trails and is well used by locals walking their dogs or just for a stroll.
"Sheffield City Council and Parks and Countryside maintain it but overall it is an area of natural beauty for people to enjoy. Unfortunately, this area has recently fallen foul to a group of people who have decided that the woods would be a great place for a motorbike dirt track, and have taken it upon themselves to chopping down trees - digging large holes and setting fires to try to clear the land in order to create jumps, banks and turns.
"I have been on site with a representative of Sheffield City Council and concerned local residents. I have put up some signs, together with the council, warning against any further damage or any off-road motorbikes riding in the area, and we shall be conducting regular foot patrols into the woods in an attempt to catch these people.
"May I ask that if anyone is in the area and sees any damage being caused in the woods that they do not hesitate and contact us straight away. Let’s keep this area of natural beauty safe and beautiful for people who want to enjoy it."
Call South Yorkshire Police on 101.