During the Second World War, German saboteurs operating against Britain designed a range of unconventional bombs disguised as, amongst others: tins of plums, throat lozenges, shaving brushes, batteries, wood, coal and stuffed dogs. Arguably the most unconventional bomb was the chocolate bar bomb that was intended to be smuggled into the homes of the Royals with the purpose of assassination.[citation needed] None of the chocolate bars reached Britain, but British authorities did capture some in places as far away as Turkey, according to the MI5 file "Camouflages for sabotage equipment used by the German sabotage services". A secondary use for the proposed disguised chocolate bar was as an emergency hand grenade. According to MI5, the German weapons were similarly ingenious as those invented by Britain's Special Operations Executive, detailed in a series of files which had already been declassified in 1999. The bomb was made of steel with a thin covering of real chocolate. When the piece of chocolate at the end was broken off, the canvas detonator was pulled, and, after a delay of seven seconds, the bomb would explode. To kill a member of the British royal family, the bar would have had to be smuggled into the residence by the saboteurs themselves or smuggled into a box that would have been taken into the palace from an ordinary source. None of the saboteurs got close enough to London to carry out the Nazi plan. These ingenious objects got no further than four explosive cans of peas, which were found on German agents who landed in Ireland by small boat; the agents claimed that they hoped to get them into Buckingham Palace. Why a member of the royal family would be opening a tin of peas themselves, however, doesn't seem to have been taken into account.

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