The Second Phase Offensive (25 November – 24 December 1950) or Second Phase Campaign (Chinese: 第二次战役; pinyin: Dìèr Cì Zhànyì) of the Korean War was an offensive by the Chinese People's Volunteer Army (PVA) against United Nations Command (U.S./UN) forces, most of which were soldiers of South Korea and the United States. The two major engagements of the campaign were the Battle of the Ch'ongch'on River in the western part of North Korea and the Battle of Chosin Reservoir in the eastern part of North Korea.