A man who went missing and was found by a police drone up to his armpits in water said he was "lucky to live".
A major search was launched for Peter Pugh, 75, from Brancaster, Norfolk, after he disappeared following a walk home through fields on Saturday at about 17:10 BST.
It was only when a drone was sent up that Mr Pugh was spotted in dense reed beds at Titchwell Marshes on Sunday.
Police said the technology was key in helping them find him quickly.
Recovering in hospital, Mr Pugh said he knew the area well and decided to plough on through fields despite the ground becoming unstable, thinking it would improve further ahead.
After tripping and falling a few times he took a rest but by about 21:00 the tide was starting to come in and his attempts to swim to the next field were hindered by reeds.
Image captionPeter Pugh with his wife Felicity said they were extremely grateful to the emergency services
"I kept trying to escape but couldn't. I couldn't crawl because my feet got stuck and if I stood up and tried to walk, the same, they got stuck.
"So I thought at some point, hopefully, they'll start looking for me," he added.
He said he could hear the helicopters overhead but thought they would struggle to see him because of the thorny grass and reeds.
"I have to admit I thought I'd be lucky to live, because I'm 75 and my heart's not going to be enjoying this," Mr Pugh added.
He drank reed water overnight but cannot remember being rescued.
"It was such a shock to my system," he said.
Image captionThe reed beds at Titchwell Marshes
He was taken to the Queen Elizabeth Hospital in King's Lynn where he was treated for hypothermia.
His wife said she had nothing but praise for the "wonderful" emergency services.
"The emergency services and technology saved his life but he stayed alive because he was so fit," Mrs Pugh said.
His rescue she added "was like a miracle".
Image captionEmergency services including the coastguard and local lifeboat were involved in Peter Pugh's rescue
Sgt Alex Bucher from Norfolk Constabulary said: "Without the police drone we would not have been able to locate him in the time we did.
"It allows us to search areas that are difficult to access and within close range where a helicopter may not be able to get."
Mr Pugh went missing for 22 hours and 50 people, a police helicopter, HM Coastguard and a lifeboat from Wells took part in his search.