Police want to talk to anyone who witnessed a fatal dog attack on Collingwood Beach in March, or anyone who has encountered the dogs involved previously.
Superintendent Greg Moore said Strike Force Beaks had been formed to investigate the attack and surrounding circumstances.
"This is heartbreaking for the family of the people involved in the attack," he said.
"They were good people out for a Sunday walk. That's one of the motivations for our investigators to do the best job they can to prevent any similar incidents happening.
"We believe there are witnesses out there that may have information about the care and control of these dogs in the weeks and months leading up to these attacks that may be helpful."
Just after 7am on Sunday, March 29, emergency services were called to Collingwood Beach, off Elizabeth Drive at Vincentia, following reports of a dog attack.
On arrival, NSW Ambulance paramedics located five people suffering lacerations and bite marks.
They were all were treated, however a 91-year-old woman suffered serious injuries and died at the scene.
A 47-year-old man and three women - aged 29, 73 and 79 - were taken to Shoalhaven District Hospital in a stable condition. They have all been released, however, the two older women are recovering from their injuries at home.
Three dogs were seized nearby by Shoalhaven City Council Rangers and destroyed.
Police said the owners have been assisting them with inquiries.
If you have any information, or previous contact with the dogs, please contact Nowra Detectives on (02) 4421 9699 or Crimestoppers on 1800 333 000.
Superintendent Moore encouraged all dog owners to take responsibility for their animals.
"This is a timely reminder for all dog owners to ensure their dogs are secured on their property and under adequate control at all times," he said.
Two of the dogs are described as being bull-mastiff cross breeds, of medium-sized and brindle in colouring. The third is a bull-mastiff cross breed of medium-sized and white with brown patches.