Action is being taken to stop children's play areas being used as training grounds for dangerous dogs.

Irresponsible owners are forcing fighting dogs to clamp their teeth around the seats of swings, then dangle in the air, to strengthen their jaw muscles and make them more aggressive.

Sutton Council estimates the so-called status dogs are damaging three seats a month, costing taxpayers more than £6,600 a year.

The damage also often exposes the swing’s metal core, sparking fears children could be hurt on them.

Now Sutton is fighting back by trialling swing seats with insect repellent citronella baked into them, to try and keep dogs away.

Councillor Simon Wales, Sutton Council’s executive member for communities, said: “Not only is the problem expensive, it’s also extremely dangerous.

“The seats we are trialling are made with oil of citronella baked into the black rubber mix. When dogs bite into the material, it leaves an unpleasant taste which dogs are known to dislike.

“The seat mixture is unpleasant but not harmful to the dogs; it's only a pity we can't find a repellent for the dog owners who degrade their animals in this way.”

Citronella is used in household products including perfumes and candles, and is harmless to humans.

It has been widely used as an insect repellent for the past 50 years.

The council is also working closely with the police to crackdown on the problem and is calling on residents to immediately raise the alarm if they spot dogs in playgrounds.

It is also pressing for a change in the law to allow councils to take tougher action against irresponsible dog owners.

Councillor Wales said: “Owning a dog is a rewarding experience but it is also a big responsibility - and councils should have proper powers to combat those who abuse that responsibility.”

To report a problem call the council on 020 8770 5070 or the safer parks police on 020 8721 2268.