KEY POINTS:
A badly injured caver 3km inside one of New Zealand's deepest and longest cave systems could be stuck underground for two days.
Police and search and rescue staff are part way through an attempt to free Motueka general practitioner Michael Brewer, 47, from inside the Greenlink-Middle Earth cave system beneath Takaka Hill.
Dr Brewer suffered head and leg injuries when a rock hit him as he was surveying and mapping the cave system with three companions about 5pm on Saturday.
"He was climbing a rock face and our information is that a dislodged rock knocked him off that," said Tasman police district search and rescue co-ordinator Hugh Flower.
"He fell and suffered head injuries and leg injuries."
Dr Brewer spoke to his wife, Sarah, by cellphone yesterday. "We managed to talk to Michael not long after they got the communications in there," Mrs Brewer said. "He sounds quite cheerful and it was great to hear his voice."
A caver herself and usually part of search and rescue teams, she is staying on the surface with the couple's two teenage daughters.
Mrs Brewer said the family were "very relieved" to hear that her husband's condition had not deteriorated overnight.
It could be more than two days before he is removed in what rescuers say is the biggest caving rescue since 1999.
The Greenlink-Middle Earth cave system is listed as the country's 10th-deepest (394m) and 14th-longest (5228m) on the New Zealand Speleological Society website.
Dr Brewer is trapped near New Zealand's deepest shaft, Harwood's Hole, an area notorious for troubling even the most experienced cavers.
Ironically, he was one of those involved in the 1999 rescue, which took three days to get a caver from 5.5km inside caves in the nearby Mt Owen.
Mr Flower said: "He's usually one of the first people we call for cave rescues. A lot of people here know him. Their concern is to get him out and get him out safely."
Dr Brewer is described by cavers as an asset to the sport, thanks to the "rare" combination of his medical expertise and caving experience.
One person stayed with him as the others went for help, Mr Flower said, but the caves are so intricate it was 11pm before they raised the alarm.
The rescue involves 60 people, including 30 specialist cavers flown in from Auckland, Hamilton, New Plymouth, Wellington and Christchurch. The operation had cost $20,000 by last night.
Mr Flower said rescuers and medics went into the caves, reaching Mr Brewer yesterday morning, and another crew with radio communications arrived about 5.30pm.
"He's on some painkiller medication. He's lucid, he's comfortable. He may have a pelvic fracture ... He's in a pretty tightly squeezed space at the moment so it's a matter of slowly getting him out by relay - hand to hand, pass-the-parcel-type stuff."
Mr Flower said the recovery would be slow and details of how it would unfold were still being worked out last night.
"I've got a cross-section of the caving system and it's all ups and downs and sideways and narrow pieces and rock pools," Mr Flower said.
"Some of the sections are called 'squeeze' ... which gives you an idea. It's pretty tight getting through some of those.
"They've taken a stretcher down there. We don't know if we can even use the stretcher to get him through some of those narrow pieces.
"It's a case of him being manhandled basically, from person to person. It's going to take us a good couple of days or more to get him out. It's a biggie."
Auckland Speleo Group president Paul Rowe said eight Auckland cavers had gone to assist with the rescue.
"It is stressful to think that someone you know is injured. Everybody wants to pull together and try to help."