A metal detector enthusiast sparked a major emergency rescue operation when he waded out from a beach in search of a possible bomb.

Arthur Wigley returned to an area on Grain off the Thames Estuary last night where he said he had earlier unearthed a cluster explosive.

A concerned passer-by spotted him walking into the water around 8pm and when they did not see him return, called police.

Officers went to the area alongside Kent Fire and Rescue, Kent and Medway Coastguard, Sheerness RNLI lifeboat and South East Coast Ambulance Service.

HM Coastguard's helicopter was scrambled from its base in Lydd to assist the search in tracking down the 65-year-old, who was soon located unharmed, not realising what had happened.

The Rochester-based maintenance engineer reported finding a potential 11-inch shell and suspected cluster device with detonators to police on August 12.

A Royal Navy team from Southampton was dispatched the following day, but could not find anything to match his description.

Mr Wigley said he was fearful because the munitions may have come from the SS Richard Montgomery – the US liberty ship loaded with explosives which sank off Sheerness in August 1944.

Known as the "American bomb ship", the wreck remains a danger to shipping in the estuary. He said the potential explosive could also be hazardous to children who play on the beach.

On a return visit to the area, he saw a grounded boat on the shore side.

He said: "If it had been a bomb and it had gone off and there were people on board they would have been blown to bits.

"I think them coming to rescue me like that was a bit OTT.

"I have been to that area several times since I took up metal detecting during lockdown and I know the tides and when it's safe.

"Perhaps they should have spent more time looking for the possible cluster bomb."

Maritime and Coastguard Agency spokesman Stuart Appleby confirmed the scale of the emergency services response and said: "The person was identified safe and well. No search and rescue assistance was required."

It is understood weapons dating back to the Crimean War were routinely dumped in the estuary when no longer of use.

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