A home-help nurse alerted the police at 9.37pm on Sunday evening after entering Feste's apartment and finding her dead body in the vicinity of the bedroom. The victim had suffered severe head injuries.

“We understand that people are anxious,” said police prosecutor Asbjørn Onarheim.

“But on an everyday level, I don’t think there’s any particular cause for anxiety.”

A 42-year-old man arrested and charged in connection with the murder was released on Tuesday after police found no evidence tying him to the crime.

A number of independent witnesses told police the 42-year-old was at his mother’s home on the evening in question.

Police arrested the man at his mother’s apartment, located around a hundred metres from the murder scene, after receiving reports of a domestic dispute later on Sunday evening.

A number of family members said the 42-year-old old and his younger brother had started fighting over a disagreement about money.

The nurse who found the body arrived at Feste’s apartment after the older woman had put out a call for help using her medical alarm.

The home-care nurse told police she saw a man, aged 30 to 40, inside Feste’s apartment just moments before she arrived at the building.    

Os mayor, Terje Søviknes, said the council would do all it could to assist the residents of Oshaugen, staff at the elderly care facility, and the relatives of the deceased.

“We’re doing what we can to create a secure environment for the residents at Oshaugen,” he said.

Søviknes added that the council had brought in extra staff, both to assist residents being questioned by the police and to make them feel safer.

“It’s difficult to imagine that something like this could happen in Os. It’s a gruesome act. All we can do is stay calm and rely on the police to commit the necessary resources to enable a swift resolution of the case.”