In 1963, fighting between Egyptian forces and British-led Saudi-financed guerrillas in the Yemen Arab Republic spread to South Arabia with the formation of the National Liberation Front (NLF), who hoped to force the British out of South Arabia. Hostilities started with a grenade attack by the NLF against the British High Commissioner on 10 December 1963, killing one person and injuring fifty, and a state of emergency was declared, becoming known as the Aden Emergency.