The Royal Military Police (RMP) is the corps of the British Army responsible for the policing of service personnel, and for providing a military police presence both in the UK and while service personnel are deployed overseas on operations and exercises. Members of the RMP are often known as 'Redcaps' because of their ubiquitous scarlet-topped peaked caps, or scarlet coloured berets. During the First World War the Military Police grew from 508 all ranks to over 25,000 all ranks by the end of the War. During the Battle of Neuve Chapelle in March 1915 the Military Police served the Army as a whole rather than just individual units. On 27 February 1926 the Corps of Military Police was formed by merging the Military Mounted Police and the Military Foot Police. During the Second World War the Military Police grew from 4,121 all ranks to over 50,000 all ranks within six major branches of specialists: Special Investigation Branch - The S.I.B. was first formed in 1940, with 19 detectives from the Metropolitan Police transferred to the Army for deployment in France.