Specialists airlifted into remote areas of Kosciuszko national park as search for hiker enters sixth day

Friends last saw missing man Hadi Nazari, 24, descending the Hannels Spur Trail on Thursday

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The search for a 24-year-old hiker missing in Kosciuszko national park since Boxing Day has entered its sixth day, with the man's sister expressing fears about potential threats to his safety.

Hadi Nazari, an experienced hiker whose birthday was on Tuesday, has not been seen since, when friends had descending the Hannels Spur Trail at Geehi, between Khancoban and Thredbo, on Thursday.

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