Minneapolis police regrets Australian woman's shooting
Damond was shot dead on July 15 as she approached a police car after reporting a suspected rape.
A lawyer representing Damond's family said suggestions that the two officers feared an ambush were "ludicrous."
Her death has attracted widespread condemnation.
Minneapolis police shoot Australian woman dead
Who was Justine Damond?
Damond, 40, hailed from Sydney, Australia. She was living in Minneapolis with her fiancé Don Damond. The two were set to be married in August. She originally trained to be a veterinary surgeon but worked as a motivational speaker, meditation teacher and healer.
Officer Mohamed Noor shot Damond as she approached police car
At around 11:30pm, police officers Matthew Harrity and Mohamed Noor responded to Damond's 911 call about a suspected rape in an alleyway near her house.
Damond approached the police car, whose lights were turned off, dressed in her pyjamas.
Harrity told officials that following a conversation, Officer Noor shot Damond.
No weapons were found at the scene.
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Officer said he was startled by 'loud noise near car'
Minnesota Bureau of Criminal Apprehension (BCA), which is leading the investigation, said "Harrity indicated that he was startled by a loud sound near the" car.
The officers also mentioned hearing a loud noise in a police recording of the incident, which is suspected to be fireworks.
Neither Noor, nor Harrity had their bodycams turned on. Their car's dashboard camera too didn't capture the incident.
Australian PM Turnbull: 'We're seeking answers'
Australian PM Malcolm Turnbull condemned the incident. "It is a shocking killing, and yes, we are demanding answers on behalf of her family," he said. "How can a woman out in the street in her pyjamas seeking assistance from the police be shot like that?"
Damond family lawyer calls ambush fear "ludicrous"
Officer Harrity's lawyer Fred Bruno said: "It is reasonable to assume an officer in that situation would be concerned about a possible ambush."
The Damond family's lawyer Robert Bennett responded to this saying Justine, who was in her pyjamas as she approached the squad car "was not a threat to anyone."
He said the ambush fear is "ludicrous" and "disinformation."
What happens next?
Investigation into shooting to take four months
The BCA will take up to four months to complete its investigation into the incident. Prosecutors will then decide whether to charge the police officers.
Police Chief Harteau said the killing was the "the actions and judgement of one individual."
Both officers have been sent on paid administrative leave.
Officer Noor has refused to be interviewed by investigators, as per his legal right.
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