On July 7, 1937 Japanese forces on maneuvers near the Marco Polo Bridge in Peking occupied Wanping County on the pretext of looking for a missing soldier. Chinese troops stationed in the area resisted fiercely.
一九三七年七月七日，日軍在北平蘆溝橋附近演習，藉口搜查失蹤士兵，襲擊宛平縣，駐軍奮起反抗。