A 71 year old woman has been mauled to death by her dogs in her backyard garden.The five animals pounced on Gloria Knowles, 71, after she went into the garden to give them their evening meal.The widow was badly injured when the dogs – two 'giant' Bordeaux French mastiffs, two American bulldogs and a small mongrel – seemed to suddenly turn on her.She was found dead at the scene in Morden, South London on Tuesday night.Currently, police can only prosecute owners of dogs who harm people if the attack happens in public - and they can only forcibly remove illegal dogs.However calls have been made for the Department for Environment, Food and Rural Affairs (DEFRA) in the United Kingdom to change the law to allow dog control rules to apply everywhere.The Communications Union CWU, which represents postmen, is campaigning to change the law and said the Dangerous Dogs Act 1991 is failing to protect both dog owners and attack victims.