Emergency services were called to a track near Rectory Lane in Brantham on Wednesday morning, July 24, shortly before 6.30am.
Anita Rose had left her home around 5 a.m. to walk her dog, a springer spaniel named Bruce, but she was found unconscious lying on a railroad track near the sewers and the railroad tracks.
She was taken to Addenbrooke’s Hospital but died on Sunday morning, July 28.
Suffolk Police treated the attack as attempted murder and arrested a 45-year-old man from the Ipswich area on Saturday afternoon. He has since been re-arrested on suspicion of murder.
A 37-year-old woman, also from the Ipswich area, was also arrested on Saturday on suspicion of handling stolen goods in connection with the incident.
Officers were also able to locate and recover the missing mobile phone – an Apple iPhone. The pink zip-up jacket, which police believe Anita was wearing just before the incident, is still missing.
The couple were taken to Martlesham Police Investigation Centre for questioning and released on bail with conditions to return on October 25.
In a statement, Ms Rose said: “Our mother was well known and loved in the community.
“She was taken from us so abruptly, far too soon, and we were deprived of so much time with her.
“She was not only a mother of six children, she was also a grandmother to 13 others, a long-time partner, a mother-in-law and a special friend to so many.
“Someone, somewhere, must know something, and we encourage them to come forward.
“We want to thank everyone for their love and support.
“All we ask is that everyone cherishes the time spent with their family and loved ones.”
Detective Superintendent Mike Brown said: “This was a very serious incident as a result of which Anita sadly died as a result of her injuries.
“The family continues to be supported by specially trained police officers as part of the investigation.
“The investigation to establish all the circumstances surrounding the offence is continuing, as are the investigations to establish the cause of death.
“Although I can now confirm that the scene has been lifted on Rectory Lane.
“Local residents should expect a continued police presence over the coming days as investigations continue, while additional officers will also be present in the area to reassure the local community.
“While the searches and door-to-door enquiries take place, we are keen to speak to anyone who saw anything on Wednesday that could assist the police investigation and anyone living in the area who has CCTV cameras or doorbells.”