The children of a woman allegedly murdered in her Adelaide home more than two decades ago say they are relieved an arrest has been made.

The body of Phyllis Harrison, 71, was discovered with multiple stab wounds at her Elizabeth South home in March 1998.

The case has been unsolved for more than 22 years, but police on Thursday arrested and charged a 45-year-old man.

“The arrest happened this morning and the suspect will be before court tomorrow morning, in the Adelaide Magistrates Court,” SA Police Assistant Commissioner Peter Harvey said.

He said the arrest was the result of a collaboration between Major Crime detectives and forensic experts.

However, he said he was prevented from providing details about the man’s identity because of legal restrictions.

Speaking to police after the arrest, Ms Harrison’s children said they have been brought closure.

“It was a great injustice that we lost our mother,” her son Dean Harrison said.

“We do feel relieved that it can’t happen again. There can’t be any more.”

Phyllis Harrison’s children Dianne Smoker, Julie Lane and Dean Harrison. Photo: SA Police

Ms Harrison’s daughter, Julie Lane, said her mother’s legacy was the close family she left behind.

“The family’s been wonderful, we’ve all banded together,” she said.

“We just got closer and closer as time went by.”

‘Now is the time to come forward’

Assistant Commissioner Harvey said Ms Harrison had been confronted in her home.

“The house was ransacked and it’s really unclear, even to this day, whether anything was taken,” he said.

“A knife was found nearby. It matched the type of attack that happened, and that is, of course, retained by the police.”

Ms Harrison was last seen walking her dog at 7.30pm the night before her body was discovered by her daughter and grandson.

Assistant Commissioner Harvey said the experience was traumatic for family members.

“You could imagine the shock that a family has, walking into their grandmother’s and mother’s house and finding her deceased, not just from natural causes but stabbed to death,” he said.

He said the family had described “unfathomable relief, but also sadness” at the arrest.

The Assistant Commissioner said the arrest was made as a result of Operation Persist, which investigates unsolved cold cases.

Ms Harrison’s daughter and grandson found her body. Photo: ABC News

“This is what drives the detectives, the South Australian police, to keep going,” he said.

“This is 22 years of work.”

He also appealed to the public for any outstanding information on the case.

“There might be some more information out there,” he said.

“There might be someone who knows something, who is reflecting on something they saw or heard in the past 22 years.

“Now is the time to come forward – it’s the right thing to do.”

A $200,000 reward is still on offer for information that leads to a conviction.

–ABC