Ms Balmain was last seen in the Kingsford area on November 5,1994,and was reported missing later that evening.
Two days later,a cork-heeled platform shoe,her cane make-up bag,diary and keys to her Bellevue Hill unit were found scattered across four Kingsford streets.
Despite extensive investigations by local police at the time and over the years,no one has been charged in relation to her disappearance.
In 1999,an inquest found that Ms Balmain died at the hands of a person or persons unknown,and the matter was referred to the unsolved homicide unit for future investigation.
A formal review was conducted last year and the case was assigned to a senior detective for re-investigation under Strike Force Aramac.
In May, as part of a renewed appeal to the community for any information that may assist investigators.
In a statement on Thursday,NSW Police revealed several reports have been received with relevant information,and investigators are in the process of assessing the information and identifying all lines of possible further inquiry.
Among the information sent to investigators is a photograph of a man they wish to identify and speak to about Ms Balmain’s last movements.
Strike Force Aramac lead investigator Detective Chief Inspector Stuart Bell said the image was sent to investigators anonymously following the reward announcement.
“It is believed that this image was taken some time in the mid-2000s,but that the individual depicted may have information that would help us progress our investigation,” Chief Inspector Bell said.
“It is our hope that someone in the community may recognise this man so we can speak with him and ensure all possible avenues of inquiry are followed through.”
He said anyone else who may have information on Ms Balmain’s disappearance is encouraged to come forward “so that we may finally provide answers to her family”.
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