‘It could knock a whole street down’: the art of defusing a second world war bomb

Everyone at Exmouth Marina knew there was an unexploded German bomb in the water. Old hands at the dock had been saying so since the end of the second world war. But the marina had been dredged and re-dredged and nothing had ever come up. It had started to sound like an old wives’ tale. The marina is a busy stretch of water: a commercial port until the late 1990s that had since been converted into a home to private yachts. A bomb, you’d think, would have a hard time staying hidden. But in the middle of the afternoon on Wednesday 14 January 2026, 81 years after the end of the second world war, Steve Hockings-Thompson, the manager of Exmouth Marina, got a call from the crew of a dredging vessel telling him he’d better come out to the boat. “I thought: ‘Oh crikey. We’ve got a bit of an issue here,’” Hockings-Thompson told me recently.He went out to the dredger, a squat barge that hauls silt and other debris from the marina floor on to a flat deck that resembles a steel sieve. Sitting on the deck was a huge hunk of metal, caked in mud and stones. As Hockings-Thompson got closer and saw its distinctive conical shape, he knew it was a bomb – a big one. The dredger was loaded with 20,000 litres of diesel fuel, so if the bomb detonated, it would be disastrous. He called the police, who quickly came to the scene. “And then,” he said, “all hell broke loose.”To deal with the explosives, they called in the army. The call was picked up at the control centre at Vauxhall Barracks in Didcot, a small town in Oxfordshire. This is the headquarters of the 11 Explosive Ordnance Disposal and Search Regiment (11EOD), a specialist army division responsible for all kinds of bomb disposal – from improvised devices planted by terrorist groups to second world war-era munitions.When the Exmouth bomb was called in, Maj Andrew Boyce, who was managing operations for the regiment, was confused. “We were talking about ‘the bomb’, which I’d been told was a 50kg,” he recalled. “And then somebody on the phone tells me it’s a 250kg. I’m like, how have you confused a 50kg bomb, which is the size of a fire extinguisher, with a 250kg bomb, which is the size of a hot water tank?”The reason for the confusion soon became clear: the Exmouth Marina bomb was not the first to be discovered that day. Another second world war bomb had been unearthed a few hours earlier at a building site in Plymouth, 50 miles away.In Plymouth that morning, Luke Templeton, director of S.I UXO, a private contractor that goes in ahead of construction companies to look for unexploded bombs, had known what he was looking for. His company’s historians had already spent a fortnight doing a detailed risk assessment of the site, drawing on historical documents showing the Luftwaffe’s flight paths and local records of airstrikes. From this, they’d worked out that it was highly likely there were two bombs buried somewhere on the building site. Using specialist equipment, they had found a 50kg bomb buried more than four metres down. After inspecting the bomb up close, Templeton called the police.As far as Boyce knew, this was the first time since the immediate postwar period that two unexploded bombs had been discovered on the same day. The two bombs were in the same part of the country, and had been reported to the same police force, Devon and Cornwall. “We’re used to having confusion with location or devices. We’re not used to having two devices,” said Brig Darren Fisher, who at the time was a colonel overseeing the operations. Once the confusion had been straightened out – it was a 50kg bomb at the building site in Plymouth, and a 250kg bomb floating on the dredger in Exmouth – the response began.When most people think of bomb disposal, they imagine a lone figure in a bomb suit carefully approaching an improvised device as bullets fly overhead, holding steady as they unpick wires, knowing that one wrong move will kill them. This image was forged in Belfast during the Troubles and Helmand province during the invasion of Afghanistan, and it is not unwarranted; bomb disposal is commonly described as the most dangerous job in the military. But, in Britain in 2026, the daily reality of the job is quite different.Although the same team deals with terrorist incidents, such as the 2017 Manchester attack on an Ariana Grande concert, it is unexploded second world war munitions that make up the core work of the UK’s bomb-disposal teams. The Luftwaffe dropped more than 60,000 tonnes of bombs on Britain over the course of the war, and the Ministry of Defence estimates that roughly one in 10 of these failed to explode on impact. The reasons range from the grim – poor manufacturing quality due to a reliance on forced labour in concentration camps – to the prosaic: a bomb might have landed at an odd angle, or on soft ground that absorbed the impact before the fuze could fire. (“Fuse” is the general spelling for electrical safety devices and burning cords, while “fuze” refers to engineered explosive detonators.) Britain also dropped munitions on its own land during training exercises and deliberately buried surplus after the war in an effort at disposal. Eight decades on, the physical remnants of the war still account for about 2,000 of the 2,500 incidents that military bomb-disposal teams respond to in an average year.The calls often come in from metal detectorists and magnet fishers, hobbyists who throw strong magnets into waterways to see what comes up. They surge on bank holidays, when people are out walking and notice things underfoot, or catching up on tasks such as clearing out a grandparent’s home. Not long ago, the bomb-disposal unit was called to deal with a 2in mortar that had been used for 20 years as a paperweight. Increasingly, calls come from construction sites, as buildings get taller and companies dig deeper, which has led to a growing industry of private contractors actively searching for unexploded bombs. “We’re expanding cities, building new homes, and an accident could happen,” said Templeton. “If a 250kg bomb went off in a city, it could knock a whole street down.”The passage of time has not rendered these explosives less dangerous. In June 2010, three bomb-disposal experts in Göttingen, Germany, were killed by a 500kg American bomb found beneath the site of a new sports arena. In 2020, a 250kg bomb exploded beneath a crab boat off the Norfolk coast, seriously injuring five of its seven crew. In 2021, another bomb exploded beneath a drilling rig near Munich’s main railway station, injuring four. Because it was a global war, this is a global problem. This year, a second world war bomb beneath a stilt house in Indonesia detonated, killing five people and injuring 20.These decades-old devices are difficult to read or predict. “You don’t really know why [a particular bomb] didn’t function, which is part of the problem,” said Lt Col Andy Hambley, the commanding officer of 11EOD. Years of corrosion, shifting ground and rust make the fuzes less predictable, the machinery harder to read.That was exactly the issue facing two teams in two different corners of Devon on the afternoon of 14 January.At about 1pm, PO Scott Dooley, a diver and bomb-disposal operator with the Royal Navy’s Diving and Threat Exploitation Group, arrived at the building site in Plymouth. Dooley, a tall man with a neatly trimmed beard and a soft Devon accent, grew up in the military; his father was in the Royal Engineers, doing bomb disposal. In recent years, he had acquired the nickname “the Doom Watch”, because every time he was on duty, the phone didn’t stop ringing (his record was 11 call-outs in a single week). In Plymouth, Dooley scanned the area for risk: there was a school nearby, as well as a glass-fronted hotel that could shatter if the worst happened. Police were already at work establishing a cordon and evacuating the area around the bomb.When an operator approaches a bomb for the first time, they do not know what they are walking towards. The most important thing is to assess the fuze, a metal cylinder screwed into the side of the bomb. It is the first link in a chain. The fuze contains explosives, which fire a tiny, highly sensitive detonator, which sets off a booster charge, which sets off the main filling of the bomb, a comparatively stable “secondary” explosive. Most German fuzes were electrical, charged from the aircraft as the bomb was released. After 80 years, there is no charge left in them. But some German bombs were fitted with a mechanical delayed-action fuze, constructed from gears and springs, like a watch. Once triggered, this fuze ticks down before detonating between two and 72 hours later. The Luftwaffe deliberately fitted these fuzes to maximise disruption; hospitals, roads and factories were cleared for days at a time because the bombs could detonate long after impact.Everything, therefore, turns on the fuze. If the fuze is judged to be sensitive, that usually means it is too dangerous to move the device. The safest option is to surround it with sandbags and detonate it where it is. If the fuze is stable, then it can be moved somewhere safer, such as out to sea.Dooley had two things working in his favour: a 50kg bomb was less likely to have a ticker, and it was still half-buried, which suggested it hadn’t been badly jolted. On the other hand, the fuze was submerged in mud and he couldn’t see it. Bomb-disposal operators try to avoid moving a device until they’ve assessed the fuze, lest they trigger a ticker, but Dooley had no choice. Down in the pit, he and a colleague built a stable platform on a ledge of mud, surrounding it with sandbags, and set to work painstakingly unearthing it. Once it was out, he placed a listening device on it called a microphone stethoscope, or mic steth. He listened for ticking.Silence. A moment of relief, quickly followed by further investigation. Silence only means that at that moment, no mechanical fuze has been triggered. Was there one in the bomb at all?