The French warships Gloire and Victorieuse, which had been sent to Tourane (now Da Nang) to negotiate for the release of two French Catholic missionaries, were attacked without warning by several Vietnamese vessels.
Kapal perang Prancis Gloire dan Victorieuse, yang telah dikirim ke Tourane (sekarang Đà Nẵng) untuk bernegosiasi untuk pembebasan dua misionaris Katolik Prancis, diserang tanpa peringatan oleh beberapa kapal Vietnam.