Due to the high security risk of the passengers, these vehicles are often heavily secured and protected. Vehicles may be armoured by the manufacturer or an after-market specialist. (In this article the term "armored car" invariably means a reinforced civilian vehicle, not the military vehicle). When carrying an important passenger, state vehicles may be surrounded by a motorcade consisting of police or military personnel. The vehicle's driver might also be from the law enforcement or military pool; the driver of the United States Presidential State Car is an experienced agent from the Secret Service and the British prime minister is driven by a Specialist Protection officer from the Metropolitan Police Service.