Hundreds of drawing pins have been found scattered along a popular cycle path near Bridgend. The path from Brynmenyn to Blackmill forms part of National Cycle Network Route 4.
Mary John told Wales Online that she was walking the route with her father and two young daughters when she first spotted some tacks.
"As we were walking along the track I noticed some pins on the floor, so I moved them out of the way. As I carried on walking, just metres away there was more scattered again."
She continued: "Luckily, my girls were in a pram but normally they like to run around. What if a child was running and fell over, they could really hurt themselves if they fell onto the pins.
"Dogs could also walk on them. It could really cause some damage. When I got home I also noticed that pins were also on the wheels of the pram as well as on the bottom of my shoes.
"I didn't realise this until I got home, I couldn't even tell you how many I found but there were hundreds of them on the track."
John said that her discovery is putting people off using the route.
"My friend has said that she's not going to take her kids back there now as she doesn't feel like it is a safe place.”
The incident is not the first time that cyclists in the area have been targeted in such a way. In 2014, dozens of riders suffered punctures on the descent from the Bwlch into nearby Nant-y-Moel during the Valleys Velo sportive.
On this occasion, not only were the drawing pins placed on a fast descent, they were also painted black in an apparent attempt to camouflage them.