Chilling new audio has emerged of the moments around the fatal US police shooting of Australian spiritual healer and meditation coach Justine Damond in a Minneapolis alley.
The officers are heard communicating with their dispatcher over the police radio, including calling for back-up and their attempts to perform CPR on Ms Damond.
"Shots fired ... we have one down," one of the officers says.
Ms Damond's death in the alley outside her Minneapolis home just before midnight on Saturday has devastated and outraged family, friends and left the Minneapolis community upset about the latest police shooting in their city.
Her partner, Don Damond, said he was being kept in the dark about the incident.
"Sadly, her family and I have been provided with almost no additional information from law enforcement regarding what happened after police arrived," Don Damond told reporters outside their home in suburban Fulton on Monday local time.
"We have lost the dearest of people and we are desperate for information."
He said Ms Damond's death was a loss to everyone who knew her.
"Our hearts are broken and we are utterly devastated by the loss of Justine," he said.
"It is difficult to fathom how to go forward without her in my life."
Officer Mohammed Noor, who joined the Minneapolis Police Department a little over two years ago, has been identified as the policeman who fired multiple shots at Sydney-raised Ms Damond from the passenger seat of his vehicle.
The police audio was posted on the Minnesota Police Clips website.
Ms Damond, 40, called police after hearing a possible sexual assault taking place in an alley behind her Minneapolis home in what has been described as the safe, middle-class neighbourhood of Fulton.
The police audio begins with the description of a "female screaming behind the building", believed to be what Ms Damond told the dispatcher in her initial 911 call.
Ms Damond, dressed in her pyjamas, reportedly approached the driver's side window of police car when it arrived in the alley and officer Noor shot across his partner at Ms Damond more than once from the passenger seat.
The Minnesota Department of Public Safety Bureau of Criminal Apprehension, described as a fact finder independent of Minneapolis police, is investigating the shooting and confirmed Ms Damond was not carrying a weapon.
Ms Damond may have been holding a mobile phone, which was reportedly found near her body.
"BCA crime scene personnel located no weapons at the scene," BCA said in a statement on Monday.
"The BCA continues to examine evidence to determine the facts that led to the shooting incident."
The Hennepin County Medical Examiner's Office has conducted an autopsy on Ms Damond but the results have not been released.
Ms Damond, raised on Sydney's northern beaches and described as having "peace flowing through her", moved to the US after meeting and falling in love with Mr Damond, who lived in Minneapolis.
Formerly Justine Ruszczyk, Ms Damond took her fiance's surname before next month's planned wedding.
The BCA confirmed officer Noor and his partner's body cameras were not turned on and their police car dashboard camera did not capture the incident.
Minneapolis Mayor Betsy Hodges told reporters she has "a lot of questions why the body cameras were not on".
Lt Bob Kroll, president of the Minneapolis Police Federation representing officers, told AAP "the federation has decided to reserve all comment until case completion in the matter".
Teresa Nelson, interim executive director of the American Civil Liberties Union of Minnesota, said the officers violated police policy by not turning on their body cameras.
"This violation of policy thwarted the public's right to know what happened to Ms Damond and why the police killed her," Ms Nelson said.
"The two officers broke the policy not only when they didn't activate the body cameras before the incident, but also when they failed to do so after the use of force."
Officer Noor was reportedly the first Somali-American officer at Minneapolis' 5th Precinct.
The Minneapolis Star Tribune reported officer Noor had been sued once in his short career when he and two other officers took a woman, who claimed false imprisonment, assault and battery, to hospital for treatment for a mental health crisis.
Ms Damond's death has become a major national story in the US and has shone new light on police shootings in America.
The Washington Post reported Ms Damond is one of at least 524 people fatally shot by police in the US this year and and the fifth in Minnesota
The Minneapolis-St Paul area is still reeling from the acquittal last month of a police officer who shot dead a man, Philando Castile, during a traffic stop while Castile's girlfriend live streamed the horrifying incident.
Violent protests also flared after two officers fatally shot 24-year-old Jamar Clark in 2015 and were not charged.
© AAP 2017
Image: Stephen Govel