Inadvertent release? Happened all the time. Here is a bit from my book (sorry about the plug):
'Life continued with many incidents. After all, we young things were entrusted with live ordinance. I recall one night when detailed to drop bombs on the nearby air weapon range, things went horribly wrong. Naturally we could not see in the dark, especially as this was years before night vision goggles had even been invented, let along supplied. More importantly, our vintage attack aircraft were naturally not equipped with any sophisticated navigation aids. The best we could muster was Decca. As this equipment was designed for use in North Sea trawlers, sailing at best at some 20 knots, it was not surprising that it hardly coped with our attack speeds of up to 360 knots. However, despite the vagaries of our equipment, at the end of a three-hour low-level exercise around Germany, we were to drop practice bombs on Nordhorn Range, in the dark and hopefully spot on target. As we commenced are run into the range area, but with still some 30 nautical miles north of our intended target, my navigator announced “Bomb gone”, followed by the phrase “Oh f**k”. He had misjudged the Decca readings (easy to do) and released the bomb into friendly territory. How close that was to human habitation I will never know, but we never heard of it again. Maybe that was because the unintended victim was unable to complain! '