On 17 August 2006, there was a ‘class two’ incident that occurred at the Swedish atomic reactor Forsmark. A short circuit in the electricity network caused a problem inside the reactor and it needed to be shut down immediately, using emergency backup electricity. However, two of the four generators died. They disconnected, leaving the reactor in a state where the operators did not know the current state of the system. A meltdown could have occurred, such as in Chernobyl. In Sweden, the Government immediately shut down all similar reactors until the problem could be cleared up. The risks involved here are very rare but quite lethal – a core meltdown is no joke.