Police believe people are using dogs to hunt down and kill foxes in the borough.
Four foxes have been found dead in recent weeks with wounds consistent with being mauled by dogs.
On March 17, a resident reported the death of two foxes found in Furlong Close Wallington.
The very next day police were told two foxes had been found dead next to their den which had been dug out near the sewage works in Beddington Lane.
A month before a dog walker spotted two men putting a dog into a hole in the undergrowth of the Roundshaw Downs.
In December last year another person saw a fox emerge from the woods being chased by two dogs.
On two occasions Lurcher or Terrier type dogs were seen to be involved in the attacks.
There are increased police patrols in the area with officers sharing intelligence with neighbouring boroughs – Croydon and Merton.
Police have stressed the seriousness of these offences and say that action will be taken against perpetrators.
PC Heath Keogh said that it is an offence to cause unnecessary suffering to foxes and dogs.
He added: “Culprits will be prosecuted. The Met Police is treating any crime against any form of wildlife very seriously.”
Foxes are protected from cruelty under the Wildlife and Countryside Act 1981. Offenders face six months jail and could face a fine of up to £5,000.
Any suspicious activity should be reported to the police immediately on 999.