Police are investigating claims that nails and screws are being glued upright in a road to stop parents from parking in a quiet cul-de-sac during the school-run.
It is alleged car drivers who use a street in Somerset to park while they drop their children at a primary school are being targeted.
Janet Smith, 62, said: “Nails are being placed at the side of the road.
“I went there on Thursday morning and got back into my car, and turned around in the close and I thought: ‘What’s that noise?’
“I looked around and couldn’t see anything, but when I got home and when the wheel was in a different position, I could see it was a screw that was making the noise.
“Somebody is going to have a nasty accident.
“The parking isn’t dangerous and nobody is being blocked or anything like that.
“It is straightforward legal parking.
“One of the mums was told that if she didn’t stop parking there, she was going to find nails in her tyres.”
Trish Phillips, 35, who had also found a nail in the tyre of her car, said: “I’ve had a puncture.
“I was parked here and my husband found the nail afterwards.
“It is quite hard to find somewhere to park.
“We are not in a place where we can walk to school although we are in the catchment area.”
One resident, who did not want to be named, said: “During the school run, there is no room to turn around and no room to park.
“People park on both sides of the road, so emergency vehicles couldn’t go down there.”
A spokesman for Avon and Somerset police said: “We can confirm that we received a report from a woman that she discovered a screw in the tyre of her vehicle when she returned home after doing the school run.
“She believes this was deliberate.
“We are treating the incident as criminal damage and are keen to hear from anyone who may have information.”