5 .30 UPDATE:
SEARCH and rescue crews have found no trace of missing bushwalker Sean Russell lost near remote Mt Dalrymple.
As the sun set on day five of the search, Acting Snr Sgt Karl Brazier said Australian Defence Force personnel, State Emergency Service volunteers and police were continuing the search.
"ADF and SES have been searching all day," he said.
He said the search area was in rough terrain and rescue crews were "plodding along."
"There's definitely still hope of finding him," he said
UPDATE: The search is continuing for missing Marian man Sean Russell who has now been lost for four nights in dense bushland at Mt Dalrymple.
RACQ CQ Rescue has entered its 4th day of participating in the search.
The rescue helicopter has landed at the search command post in Eungella where it will ferry nine SES workers up to the top of the mountain as the search for the man enters its 5th day.
Yesterday the rescue helicopter ferried 26 army personnel from the Eungella command post to the top of the mountain, as the fleet of searchers combing the area on foot continues to grow.
EARLIER: The arrival of 40 soldiers from Townsville has lifted spirits as the search for missing Marian man Sean Russell enters its fourth day.
The 1RAR troops joined the search on Mt Dalrymple yesterday and camped there overnight.
Mackay police district Inspector Peter Flanders said yesterday's search focused on an expanded 80sq km area.
"It (the search) will continue until we are absolutely certain that we have covered every possible area where the gentleman could be and then we'll make decisions as to where the search goes to from there," Insp Flanders said.
An Australian Defence Force spokesman said the soldiers were prepared to help in any way they could.
"They (the soldiers) were provided in response to a request for assistance from QPS (Queensland Police Service) and they'll work with them and emergency services," the spokesman said.
Last night, Senior Sergeant Mark Sweetnam said Mr Russell's wife, family and friends had visited the forward command post at Eungella yesterday.
"They were given full access and information to the efforts so far and what is being done."
RACQ-CQ Rescue also assisted with a creeping line search of scrub just north of Mt Dalrymple from 11am.
The crew performed two searches yesterday, with their last ending late in the afternoon.
A Department of Community Service (DCS) spokesman said yesterday that, medically, someone could survive for three days without food and water.
"If you are an experienced bushwalker and can find shelter, preserve water or find a water source and food, then you could survive for three weeks or longer, provided you are uninjured," he said.
A comprehensive land and air search by police, SES volunteers, members of the public and both RACQ-CQ Rescue and Townsville EMQ helicopters began at 9am Sunday.
Mr Russell has been missing since about 4.30pm on Saturday.
Snr Sgt Sweetnam said information provided suggested he was in "really good spirits" when he was last seen by the group he was walking with.
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