The Pei-ta-shan Incident or Battle of Baitag Bogd Mountain (Mongolian: Байтаг богдын тулгарал; Chinese: 北塔山事件; pinyin: Běitǎshān shìjiàn; Wade–Giles: Pei-ta-shan shih-chien; alternatively Baitak Bogdo incident) was a border conflict between the Republic of China and the Mongolian People's Republic. The Mongolian People's Republic became involved in a border dispute with the Republic of China, as Chinese Muslim Hui cavalry regiment was sent by the Chinese government to attack Mongol and Soviet positions.