Broken glass was left littering the ground in a popular children's playground.
The smashed bottles were found around play equipment in Polly Park in the St Thomas area of Swansea .
Park-goers cleaned up the mess to make the area safe for youngsters, but the "friends of" group which helps to look after it is urging people to show the location some respect and keep it open for all to use
Meanwhile, police have said they have increased patrols in the area in the hope of deterring any repetition.
Hayley Gwilliam, chairwoman of the Friends of Polly Park, said the glass incident had been reported by a woman taking her granddaughter to the park.
The mum-of-two said: "It's disappointing that this has happened.
The definition of anti-social behaviour:
"We don't mind people using the park but there are bins available so people can pick up after themselves, and we hope people treat the park with respect.
"We have had vandalism before where there has been broken glass in the park - but it tends to be isolated incidents.
"When it has happened before police have increased patrols, and then it goes quiet again.
"After the last incident PCSOs were involved in getting children from St Thomas Primary to design signs for the park.
"The park is well-used by families from St Thomas."
#EastsideNPT PCSO Steve has been responding to concerns from @friendsofpollys regarding broken glass found at the bottom of the kids' slide. Words escape me. Please keep us updated. Patrols increasing at this amazing community project. @EastsideSgt ^56519 pic.twitter.com/Rb1ynOcB15
— South Wales Police Swansea (@SWPSwansea) July 13, 2019
Miss Gwilliam encouraged anybody who found something amiss at the park to report the issue so the problem could be tackled.
Established in 2014, the friends of group has worked hard to improve the play area off Kilvey Road, cutting back overgrown plants and clearing the site, as well as arranging for new play equipment to be installed, maintaining the park, and organising events and environmental action days.
