A "terrified" student needed extensive surgery to save her leg after she was mauled by a vicious dog, believed to be a pit bull terrier.

The dog's owner looked on as the unrestrained pet carried out the horrific attack on 21-year-old Maryam Mudhir, in Victoria Road, Hendon.

Stunned neighbours saw the dog lock its jaws onto its victim's leg and savage the limb for almost 20 minutes.

Miss Mudhir was dragged along the pavement, desperately trying to escape, before her cousin beat the animal off.

The owner was arrested and the dog has since been destroyed.

Speaking from her hospital bed, Miss Mudhir said: "I feel traumatised and every time I close my eyes I can see that dog.

"It was so strong and was shaking its head as it held on to my leg.

"I was shouting and screaming, and struggling to get away, but every time I tried, it was making the wound worse."

Miss Mudhir, who is in her final year studying business management at Middlesex University, was walking to work at about 10am on Sunday when the dog started to follow her.

She tripped and fell to the ground and then the dog pounced. Its owner, a 22-year-old woman, was seen screaming among the crowd, but did nothing to control the animal.

Miss Mudhir added: "I was calling her to tell her dog to stop. She could have called the dog back, but she didn't."

Abdulatif Ubwa, 23, Miss Mudhir's cousin, eventually fought the dog off with a toaster. He said: "When I approached the owner afterwards to ask her why she didn't help, she became quite aggressive."

Mr Ubwa was bitten on the finger by the dog, and also required surgery.

"She had an animal that she couldn't handle. It was so strong, it took a lot of police to control it."

Police and specialist dog handlers arrived and arrested the owner, before taking the dog away to be destroyed. She has been bailed to return to police in March.

Miss Mudhir was taken by ambulance to the Royal Free hospital, in Hampstead. She needed extensive surgery and skin grafts to repair severe bite wounds, and faces a long process of rehabilitation.

"I am always going to feel scared of dogs, and this scar is always going to remind me of what happened," she said.

Doctors told her if a young child had received similar wounds, they would have undoubtedly died from the injuries.

Her father, Jay Mudhir, 50, of Enfield Highway, said: "She was in a lot of pain and terrified. It was terrible, she was bleeding a lot.

"Thank goodness it didn't attack her face or her throat. It could have been fatal."

An RSPCA spokeswoman said the dog should have been muzzled. She added: "If it was a pit bull, then it is on the dangerous dogs list and the police can begin criminal prosecutions against the owner.

"Anybody who has this breed of dog needs to make sure it is in a proper environment, all its basic needs are met and it gets enough socialisation."