A prosthetic hand, jewellery and weapons ranging from medieval cannon balls to live grenades are among the items unearthed from Britain’s waterways this year.

Nigel Lamford and Jim Norton spend their weekends hurling powerful magnets on ropes into rivers and canals to extract metal objects which may have been there for centuries.

Hundreds of thousands of people from across the world have watched Mr Lamford’s YouTube channel, where the pair livestream their magnet fishing expeditions.

On Sunday, within four hours of trawling Regent’s Canal in London, they had extracted three motorbikes, five pushbikes, three shopping trolleys, a penknife, and gold jewellery worth a few hundred pounds.

Magnet fishers Nigel Lamford and Jim Norton trawl Regent's Canal for metal objects on Sunday October 11, 2020 (Laura Parnaby/PA).
Magnet fishers Nigel Lamford and Jim Norton trawl Regent’s Canal for metal objects (Laura Parnaby/PA)

Mr Lamford, who has been an avid magnet fisher for nearly two years, said he does it “for the buzz” of finding “absolutely shocking” items.

The 49-year-old said the strangest item he has found was what he initially thought was a human hand.

“It was quite worrying watching fingers poke out of the water,” he said.

He handed the find over to police, who realised it was a prosthetic which had been weighed down with a barbell.

Mr Lamford said: “Everything’s got a story, but you’re never going to know what that story is, that’s the problem.

“A friend of mine pulled up war medals, which have been reunited with the family.

“We also pulled out a cannon ball from Fotheringhay Castle, where Mary Queen of Scots was beheaded.

“I never sell anything, I give it all away to museums and things like that, because it’s history, it needs preserving.”

He added: “It’s just the not knowing what’s coming next, that’s the main buzz of it.

“You go home smelling like a canal, but it doesn’t matter. Once you have a fun day, that’s all it’s about.”

Mr Lamford’s YouTube videos have attracted nearly 29,000 subscribers as well as new recruits including Mr Norton – a prison officer at a maximum security jail.

Mr Norton, from south London, said he got into magnet fishing as a cathartic alternative to going to the gym when leisure centres closed during lockdown.

The 32-year-old, wearing thick gloves, said: “Some things can be historical, some things can be quite heavy as well – and dangerous. They can be explosive or sharp.”

Magnet fishers pull shrapnel including three motorbikes, five pushbikes, a penknife and gold jewellery from Regent's Canal in London on Sunday October 11, 2020 (Laura Parnaby/PA).
Motorbikes were among the items recovered from Regent’s Canal (Laura Parnaby/PA)

The duo, who were livestreaming their 10-hour session via Northants Magnet Fishing YouTube channel, said scrap metal collectors take most of their finds, and suspicious items are checked by police.

A coroner has warned of the dangers of the pastime though, after a father and son drowned magnet fishing in a Huddersfield canal while under the influence of cannabis.

Martin Andrews, 43, and son Jack, 19, shared a passion for treasure hunting, and their bodies were found in a stretch of canal close to the River Calder in the Cooper Bridge area of Huddersfield.

Senior coroner Martin Fleming ruled taking cannabis may have had an impact on their co-ordination, but that magnet fishing also comes with “inherent dangers” because “it is impossible to know what is at the bottom of these waters”.