This is the heroic moment a three-legged pet dog saved a family from a cobra.

Homeowner Thanong was resting on a hammock on his patio when the sinister snake emerged from his garden in Phetchabun, Thailand, on February 9.

But Thanong's alert pet pooch named Sato sprang into action to drive away the venomous intruder.

Footage shows the one-year-old canine stalwart squaring up against the cobra. Despite having only three legs, Sato was able to evade its deadly strikes. He then bit into the reptile's body and thrashed it around, causing the defeated snake to retreat from the property.

The proud owner said Sato had lost one of his legs after being hit by a truck when he was only a five-month-old puppy.

He said: 'Sato has already fought with more than 10 snakes. He is very brave. After the cobra spat venom at him, we rushed him to a vet. He is safe now.'

Researchers found that 7,000 people are treated for snake bites each year in Thailand. Suchai Suteparuk from the Division of Toxicology at Chulalongkorn University reported that 30 of those die, with cobras being the biggest killer.