People are being urged not place cleaning detergent into Camborne's fountain, which is believed to be one of the last remaining fully functioning fountains in the county and has just undergoing extensive maintenance and repair works.

In March Camborne Town Council completed the important repair works the fountain. A new pump was fitted and the complete structure, with associated pipework, was thoroughly cleaned and disinfected.

A new finer gauge mesh has been fitted to improve the suction of the water and reduce the risk of damage to the circulation pump. A regular maintenance programme ensures that the fountain continues to work well and the water is safe. The council also added smart green shrubs to the corners of the fountain to minimise the risk of trips and falls on busy market days.

Councillors were, therefore, extremely upset and disappointed that someone decided to add some kind of cleaning agent to the water last week.

A spokesman for the council said: "This may have been seen as funny, but anything added to the water affects the chemical balance which has public health implications. It could also damage the pumping mechanism.

"Each time this happens, the fountain has to be completely drained, cleaned and the chemical balance adjusted. And this costs public money. The incident has been reported to the police and the council is hopeful that the offender will have been recorded on the newly upgraded CCTV system. In the meantime, the public are kindly asked to be careful not to drop any litter, coins, soap suds or food for the birds in the fountain."