A mystery cyclist filmed part of the fatal encounter between US police and Australian Justine Damond, offering a potential breakthrough in the investigation.
Minneapolis police officer Mohamed Noor and his partner Matthew Harrity were criticised for not having their body or vehicle dash cameras on when they were called to an alley behind Ms Damond's home a week ago.
Authorities announced on Friday they had identified and interviewed a male cyclist who was spotted at the scene.
Days earlier they had asked for the mystery man to come forward.
The Minneapolis Star Tribune reported on Saturday a source with direct knowledge of the investigation said the witness filmed part of the encounter.
What he filmed was not released.
Ms Damond, 40, formerly of Sydney's northern beaches, called police about 11.30pm last Saturday after hearing a woman's screams and fearing a sexual assault was taking place.
As Ms Damond suddenly approached the police vehicle Officer Noor shot across his partner and struck Ms Damond in the stomach.
Noor has so far refused to be interviewed by the Minnesota Department of Public Safety Bureau of Criminal Apprehension, which is investigating the shooting.
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The BCA cannot be compel him to answer their questions.
Minneapolis has been rocked by what was the latest high-profile fatal police shooting in the region.
Police Chief Janee Harteau was fired on Friday and at a press conference to explain the dismissal Mayor Betsy Hodges was shouted down by protesters demanding she resign.
Medaria Arradondo, a 28-year veteran of the Minneapolis Police Department, has been tapped to replace Harteau.
He served as the department's public face for most of a week after the July 15 police shooting of Damond, while Harteau was on leave.
