Navia Van Maurik was having microsurgery last night to repair a finger on her left hand that was fractured, dislocated and suffered tissue damage.

The injuries followed an attack during which an American Staffordshire dog mauled and killed Ms Van Maurik's small Papillion, Teddy.

Neighbour Sandra Marshall and her dog, Bella, were walking with Ms Van Maurik and Teddy in Lowanna Street just before 7am yesterday when the attack happened.

The pair had taken the early morning walk with their dogs every day for the past three years.

Ms Marshall said a dog approached them with its hackles raised when the pair picked up their dogs to try and protect them.

''[It] grabbed hold of the little dog Teddy. He took Teddy and Navia down and he just continued to flick the dog around like a rag doll. I was kicking it in the head and it wouldn't stop,'' she said.

The attacking dog eventually let go of Teddy who died a short time later and ran off. Ms Van Maurik was taken to Canberra Hospital.

Graham James Louis, who said he was the owner of Storm, an American Staffordshire terrier believed to be responsible for the attack, said the incident was out of character. He said the dog had escaped on Sunday night from his Dickson home before he received a call yesterday notifying him of the incident.

''I'm still very concerned about the whole issue and at that time I was flabbergasted to say the least because it's out of his character to do things like that,'' Mr Louis said.

He said the dog had only been in one fight but acknowledged Storm may need to be put down.

A Department of Territory and Municipal Services spokesman said the dog had been seized. Domestic Animal Services is investigating the attack.