John Tooze was walking his dog Scruff on Heavers Meadow, Selhurst, on Sunday, when the eight-year-old bedlington terrier was attacked at about 11.45am.
Mr Tooze, 75, said Scruff was roaming in the park when a red coloured dog bound up and got him by the neck.
He said: "It had him in it's muscular grip, Scruff was yelping and squealing, rolling his eyes then he just stopped.
"I kept saying 'call your dog off, call your dog off,' but the owner just kept telling to me beat the dog.
"He could only restrain it by tying it's hind legs together with its leash and dragging it away backwards."
Passers-by rushed Mr Tooze and Scruff to a nearby vet in Thornton Heath, but his injuries were too severe for him to be saved.
Mr Tooze said: "The vet said Scruff's ribs were all broken after being severely crushed and his chest cavity was perforated.
"It is very upsetting, we are still crying here. He was a great part of my life, I got very attached."
The incident has been reported to police, but the owner of the mastiff, a black male believed to be in his 30s, refused to give his name before leaving the scene.
Mr Tooze said he feared for the safety of other dogs and children.
He said: "The vet said to me it is not the dog, it is the owner and that was right. They way it just bounded up and got him by the throat was absolute menace.
"It could attack another dog or a child, people need to look out because it is still out there."
(Croydon Guardian - Nov 1, 2012)
