Despite a truce agreement under the Paris Peace Accords, concluded in January 1973 after five years of on-and-off negotiations, fighting continued almost immediately afterwards. The regular North Vietnamese army and Việt-Cộng auxiliaries launched a major second combined-arms conventional invasion in 1975. Communist forces overran Saigon on 30 April 1975, marking the end of the Republic of Vietnam. On 2 July 1976, North Vietnam-controlled Provisional Revolutionary Government of the Republic of South Vietnam and the Democratic Republic of Vietnam (North Vietnam) merged to form the Socialist Republic of Vietnam.