The dog was attacked by a Staffordshire bull terrier
A Limavady woman has said a bull terrier dog which killed her family's pet in their back garden had been reported "running stray" before.
Michelle Devenney said her husband was awakened by barking on Saturday and rushed out to his garden to find the family's cross terrier being mauled.
It was killed by a Staffordshire bull terrier, Limavady council said.
"From what I hear, it got lifted before but they (the owners) got it out again," Mrs Devenney said.
She said it was lucky her children were in the house at the time of the attack.
"My wee girl, she's 19 months, maybe half an hour or an hour later she'd have been out playing in the garden. It doesn't bear thinking about," she said.
Mrs Devenney said she was told by the dog pound that the animal's owner had come forward and been issued with two fixed penalties, but did not want to take the dog back.
"My concern is what is going to happen to that dog now, is it going to be rehomed, is it going to be put into a family?" she said.
Tom Keogh, enforcement officer for Limavady Borough Council, said the council has no power to take the dog away from its owner.
He said if the owner did not reclaim it by Friday it would probably be put down. Anybody who wanted to rehome it would be made aware of its history, he said.
"We took the appropriate action - two fixed penalties for straying and licensing violations," he said.
"The complaint was responded to within 25 minutes of receiving it on Saturday and the dog was removed."
Limavady Deputy Mayor George Robinson expressed "horror and disgust" at the incident.
Mr Robinson said he had been told that the previous evening the dog "had growled and been aggressive towards a child and her mother who were out walking".
He added: "The minister for agriculture and rural development is charged with the responsibility of Dangerous Dogs legislation and I have submitted questions to the minister in the assembly.
"I have also asked the minister to state what progress has been made in the review of the dangerous dogs legislation she announced in November 2007.
"It is now imperative that the definition of what constitutes a dangerous dog is defined clearly and precisely."