A vicious dog that bit an elderly man’s face and neck in Adelaide’s north overnight has attacked before and should have been euthanased years ago, another dog owner says.

A 72-year-old man is fighting for life in hospital this morning after being bitten in the throat by the dog — a bull mastiff — at Willaston about 7pm on Monday.

media_camera The 72-year-old man was airlifted to the RAH last night. Picture: Nine News

The victim was visiting a friend’s house on Princess St when he had a fall and was bitten.

Another man claims the same bull mastiff attacked his dog two years ago in the same area. The man, who does not want to be identified, said his pet needed emergency surgery.

“It should’ve been put down years ago, I’m not surprised it’s happened again,” the man told The Advertiser.

media_camera A bull mastiff dog, similar to the one involved in the attack. Picture: iStock

“Their dog came charging at us and just attacked. (The man with the dog) admitted it was vicious, straight up.

“He said: ‘the dog shouldn’t be walked off the lead because it can’t be trusted’.”

The owner was fined $250 and given a dangerous dog collar after the incident. He covered all surgery costs.

The elderly man was flown to the Royal Adelaide Hospital where he underwent surgery last night. Police say his injuries are life-threatening.

The dog’s owners will have the animal put down later today.

A family friend said they were “stressed and upset” over the incident.

“(They’re) just working their way through it at this stage,” he said.

Gawler Mayor Karen Redman confirmed the dog had been involved in an attack in 2017 and said a “medical order” was placed on the animal.

media_camera The Princess St house where the man was attacked by a dog. Picture: Ben Harvy

“That means the dog has to be secure at home, has to be muzzled at any time.” she said.

“There were restrictions put on the dog which we believe the owners were complying with.”

Ms Redman said the dog would be destroyed today. If not, under the Dog and Cat Management Act, Gawler Council would seize the pet and put it down.

“The owners have done the honourable thing and are proceeding to have it put down today,” Ms Redman said

“My thoughts and prayers are with the family of the gentleman.”