Glass is being thrown daily onto the pitch of a grass roots football pitch - posing a danger to players who have just returned after lockdown.
Volunteers at Briton Ferry Llansawel AFC have had to clear the broken shards from the grass on the playing fields on Old Road every day for more than a week.
And witnesses said they believe they know the person suspected of being responsible, who has been spotted walking a dog on a public footpath behind goalposts.
Club secretary Stuart Williams said: "We have been doing a fair bit of work lately to get the club ready for players return, with tree felling and an extension.
"But unfortunately, someone is throwing glass over the boundary fence, and we're having to go out and make it safe for players.
"There is a footpath behind the goal and someone has been throwing it from there.
"It goes without saying how dangerous it could be if someone slides into that".
With club sports having only recently reconvened following months of lockdown restrictions, the club pitch is used throughout the week and weekend, including by academy players aged 8 to 16 and a ladies side.
And the wanton vandalism is an unnecessary frustration.
"One neighbour said they had seen an older gentleman with a dog throwing something over the fence," he said.
"They thought it might be a stone, but it turned out to be glass.
"We've spoken to local PCSOs about it and they've said they are going to patrol the area.
"It's been happening every day now for almost ten days.
"It's coming to the end of the season so we are very busy down here and it's obviously a concern for coaches and players.
"We'd just urge anyone who sees anyone doing something they suspect to be someone throwing glass onto the pitch to report it to police".
