Five rescue helicopters are searching New Zealand's South Island mountains for a British backpacker and an aircraft pilot missing for four days.
Milford Sound draws tourists from around the world
The couple's four-seater helicopter disappeared while flying in heavy rain and low cloud over the dense forest between Queenstown and Milford Sound.
The poor weather has continued to hamper rescue workers efforts.
They say the chances of finding Hannah Timmings, of Cheltenham, or the helicopter's pilot are now slim.
As the weather began to close in, the pilot radioed a nearby airfield to ask directions through the mountains.
Hikers in Fiordland National Park, which has some of the most wild and dramatic scenery in New Zealand, reported hearing an aircraft engine around the same time.
A British couple died seven miles from Milton Sound in 2002
Police said this had helped them narrow down the search area.
Milford Sound, a crystal-clear fjord about 466 miles south of the capital, Wellington, draws tourists from around the world.
A British couple died in January 2002 when their sightseeing plane hit a mountain seven miles away.
Gordon Ross, 34, his wife Angela, 29, from Shandwick, Ross-shire, two Canadian tourists, a New Zealand student teacher and the experienced pilot, were killed in the crash.
And on 30 December, 1989, two sightseeing planes, each carrying a pilot and six Japanese tourists, collided over Milford Sound.
One aircraft landed safely but the other plunged into the sound, killing all seven on board.