Jim Radford, 85, from Lewisham, was the youngest person known to have taken part in the D-Day Landings 70 years ago on June 6, 1944.
Radford was only 15 years old when he served with the merchant navy as a galley boy during the allied invasion of Normandy in World War Two, just a few weeks after leaving school.
The now-grandfather-of-five left the navy in 1954 and became an anti-war campaigner, active in groups such as Lewisham Stop the War and Veterans for Peace.
Speaking to Tom Bateman on BBC’s Radio 4, he said that he believed the Second World War was necessary to stop the Nazis, but that many conflicts since then had been “unnecessary and avoidable”.
Of his experience during the D-Day landings he said: “Like everyone else, even then in ‘44, I’d seen war films, but it’s amazing the difference when it’s real.
“The water was full of dead men. A very sad memory of D-day is all the poor devils who never made it to the beach, who were in the water with life jackets on, floating, and we hadn’t time to pull them out,” Radford continued.
“Your thought is ‘this is real, this is actually happening,” he said.
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Today, June 6, 2014, marks the 70th Anniversary of D-Day and Mr Radford will be joining hundreds of other surviving veterans in remembrance of the June 6 landings.
BBC London reporter Katherine Carpenter spoke to Mr Radford from the D-Day Museum.