An experienced caver who was trapped in a newly-discovered cavern beneath Mt Arthur for more than 16 hours has been freed using explosives.
The 62-year-old Christchurch man became stuck after he had wormed his way through a tiny passageway on his back and was unable to get back through, police said.
The man was one of a group of 18 cavers exploring the newly-discovered Pillar Cave in the Mt Arthur area of Kahurangi National Park.
Four members of the party managed to squeeze through the tiny space, which was about 80 metres underground, but the man found it "impossible to get out", Nelson Police search and rescue incident controller Malcolm York said.
Police were alerted to the incident at 9pm on Saturday.
Fellow cavers were able to pass through food and warm clothing to the trapped caver and his wife, who remained with him in the cave overnight.
Explosive experts were sent in this morning to "gently enlarge the squeeze", police said.
The pair were freed from the cave about 2pm today and flown to Nelson for a medical check.
The couple were cold and wet and the woman had minor rib injuries sustained earlier in their journey, police said.
- The Press