A security guard had to shoot dead a pitbull terrier after it turned on its owners, who were having a fight.
The couple, from Orange Grove in Joburg, had to undergo emergency surgery.
The incident occurred at about 4.45am on Sunday when Netcare 911 paramedics responded to reports that an American pitbull had attacked its owners in their home in 16th Street.
Netcare 911 spokesperson Nick Dollman said neighbours told paramedics that they heard a commotion, and that the couple were having a domestic dispute when the dog attacked the wife and then the husband.
"Emergency services and the local security company were called for assistance, and the first arriving security officer felt that he had to intervene as screams for help were heard, and he shot the dog to protect the owners. Neighbours said they heard four gunshots, and the dog died at the scene," Dollman said.
The couple are both believed to be in their 30s. The wife sustained bite wounds to her chest, thigh and arm while the husband was bitten on his back and lower legs, with tear wounds on his arms and thighs.
"Amazingly, the victims were both in a stable condition and were transported by ambulance to hospital for further assessment and treatment.
"Suggestions were made that the dog had only bitten them, as opposed to attacking them in a ferocious way as is possible with that breed. The wife was very emotional and could not believe the attack or shooting of what she kept calling "her baby", Dollman said.
The couple are being treated at Brenthurst Clinic in Parktown, and were still in theatre when The Star visited the clinic on Sunday.
Dollman said neighbours were impressed with the quick response time and thanked the security company and the police for their professional assistance.
Danie Bouwer of the National Dog Breeders' Council of SA said he believed the reason for the attack was that American pitbulls were by nature very dominant.