A member of the Royal Military Police can arrest any individual in the UK whom he or she has reasonable grounds to believe to be a serving member of HM Armed Forces and to have committed a relevant civil or military law offence. RMP personnel do not have to be on Ministry of Defence land to exercise their authority over service personnel. The RMP also have police powers over personnel of the other two branches of the Armed Forces: the Royal Navy and the Royal Air Force. The Royal Navy Police and RAF Police also have reciprocal police powers over British Army personnel.