About Bắc Lệ Ambush (Trận Bắc Lệ)
The Bắc Lệ ambush was a clash during the Tonkin Campaign in June 1884 between Chinese troops of the Guangxi Army and a French column sent to occupy Lạng Sơn and other towns near the Chinese border. The French claimed that their troops had been ambushed by the Chinese. The incident led to the Sino-French War.