The search continues for a university student who has been missing in a NSW national park since 26 December.
23-year-old Melbourne student Hadi Nazari has not been seen since he set off on a bushwalk in Kosciuszko National Park at about 2.30pm that day.
His friends last saw him as he descended the Hannels Spur Trail at Geehi, between Khancoban and Thredbo.
They started looking for him when he failed to turn up to Geehi campground as planned.
Authorities were alerted just before 9pm that night, with local police and State Emergency Service personnel launching a search on foot and by vehicle.
Specialist rescue crews, NSW Ambulance, police aerial support and other emergency services joined search efforts the next day in the rugged alpine park.
NSW Police Acting Superintendent Jillian Gibson said Nazari did not have a personal beacon, but was carrying a reasonable amount of water and camping gear and had done similar hikes overseas.
She said crews were battling hot conditions and scaling the area was difficult but volunteers would help with the search into next week if needed.
"Obviously we've got concerns for Hadi, but we also have concerns about our staff, so that's why we have medical teams on stand-by at the command post," she told reporters in Wagga Wagga on Tuesday.
Nazari's sister said the anxious wait for news has left her wanting to "go outside and scream".
"This is the biggest trauma of my life ... not seeing him for so many days, not able to talk to him for so many days," Zahra Nazari told Nine News.
She feared her brother didn't have a lot of food and water as he only planned a day walk.
"I just look at his pictures all the time and pray to God that he come back, he come back soon," she said.
Police are appealing for anyone who saw him to come forward.
Nazari is described as being Asian in appearance with a slim build and about 172cm tall. He was last seen wearing a grey long-sleeve shirt, grey pants and had a blue backpack.
