 A band of Vietnamese mounted a hit-and-run attack on the French lorcha "Espérance" during the absence of her captain, "enseigne de vaisseau" Parfait, and lured the French vessel into an ambush.Her crew of 17 Frenchmen and Filipinos were overpowered and killed, and the insurgents burned the vessel.Bonard decided that an exemplary reprisal was required.