Thousands of police officers in Britain are believed to have died during the course of their duties, but this article includes only those who were killed as a direct result of a crime or while attempting to respond, prevent, stop or solve a specific criminal act. The list is currently incomplete and misses many of those who died in more regular circumstances such as traffic collisions, as well as the many killed by air raids during the Second World War. The list also omits the more than 300 officers of the former Royal Ulster Constabulary (RUC).