Frances Embleton, 24, a law graduate from Hertfordshire, has not been seen since Saturday 22 April, raising fears that she could become the latest in a series of British backpackers to have disappeared in Australia.
Police told her family yesterday that extensive inquiries and television appeals had so far drawn a blank. Her widower father, Norman Embleton, 57, who runs a building company, said: "We're just hoping someone will recognise the face and say that they've seen her."
Ms Embleton was last seen a few hours before she was due to attend a leaving party to celebrate her return home to her family in Harpenden.
The Briton, who has spent the past year travelling and working across Australia after her graduation, failed to turn up for the party. She had been due to fly to Thailand last Monday - the day her visa for Australia expired.
New South Wales police are concentrating their investigations on reports that a distraught blonde woman - a "dead ringer" for Ms Embleton - had been seen in the 3 Wise Monkeys bar in Sydney on the day she disappeared.
A witness was reported to have told investigators that a woman fitting Ms Embleton's description had told his friends that she had gambled away her money in a nearby Star City casino. "She told them that gambling was an addiction and she'd lost all her money," he said. "My friends said she seemed pretty depressed."
Yesterday, Mr Embleton said these allegations were "a complete mystery, and surprising". He said that his second-oldest daughter Laura, 27, was the last family member to speak to Ms Embleton. He said there was "nothing untoward" in the conversation and Ms Embleton was looking forward to coming home.
Several young tourists have been killed or injured while holidaying in Australia. Ten years ago, serial killer Ivan Milat was convicted of the murder of seven hitch-hikers, including two British women - Caroline Clarke and Joanne Walters.
Last year, Bradley Murdoch was jailed for life for the murder of Peter Falconio, who was attacked in 2001 with his girlfriend, Joanne Lees. Falconio's body was never found, but Ms Lees escaped.Reuse content