Officers who shot dead Justine Damond 'may have feared an ambush'

The lawyer of one of the officers involved in the fatal shooting of an Australian woman in the US has said it is "certainly reasonable" to assume they were concerned about an ambush.

Justine Damond had called 911 twice to report a suspected sexual assault in the alley behind her Minneapolis home.

The 40-year-old approached the squad car of Mohamed Noor and Matthew Harrity when they arrived at the scene, but was shot dead by Noor when she reached the driver's door.

Harrity has told investigators that he had been "startled by a loud sound" near the car beforehand.

Fred Bruno, his lawyer, told the Star Tribune that recent cases of police deaths in the US - such as the murder of a New York City officer as she sat in her patrol car - may have made the officers feel unsafe.

Noor has refused to be interviewed by investigators and his lawyer Tom Plunkett "did not provide clarification on when, if ever, an interview would be possible", the Minnesota Bureau of Criminal Apprehension said.

In a statement, Mr Plunkett said the officer was "a caring person" who "empathises with the loss others are experiencing".

Minneapolis mayor Betsy Hodges said authorities could not "compel" Noor to speak about the incident, but said he should as "he has a story to tell that no one else can tell".

She added: "It's frustrating to have some of the picture but not all of it."

At the time of the shooting, the two officers' body cameras were not switched on and footage from the police car failed to capture the incident.

Australian Prime Minister Malcolm Turnbull described the death as "inexplicable" and said his government was trying to find out what "went tragically wrong".

He said: "How can a woman out in the street in her pyjamas seeking assistance be shot like that?

"It is a shocking killing, and yes, we are demanding answers on behalf of her family."

Ms Damond, a meditation teacher from Sydney, died from a gunshot wound to the abdomen.

The 40-year-old was due to marry fiance Don Damond, whose name she had already taken, in August.

Ms Damond's family in Australia said they were "trying to come to terms with this tragedy and to understand why this has happened".

On Wednesday, hundreds of family members and friends gathered for a vigil on Sydney's Freshwater beach, where they stood in silence before casting pink flowers into the water.