Don Damond, 50, made the statement outside his Minneapolis home where his fiancee, 40, was gunned down by a local police officer on Saturday night after calling 911 for help.
Mr Damond’s first public comments come as the officer who shot Ms Damond has also broken his silence, and audio captured by Minneapolis emergency dispatch files reveal how quickly the shooting happened.
The Sydney woman’s grieving partner revealed she had called 911 on Saturday when she heard noise in the alley behind the family home.
“Our hearts are broken and we utterly devastated by the loss of Justine,” he said.
“As you know, it was Justine who called 911 on Saturday evening, reporting what she believed was an active sexual assault occurring nearby.”
Mr Damond was damning of police officers, saying the family have been provided with “almost no additional information from law enforcement regarding what happened after police arrived”.
“We’ve lost the dearest of people and we’re desperate for information,” he said.
“Piecing together Justine’s last moments before the homicide would be a small comforts as we grieve this tragedy.”