Five French soldiers and a dozen coolies, [clarification needed] too impatient to wait their turn to cross the river by junk, tried to swim across and were carried away by the strong current and drowned.

At 9:00 am the brigade's advance guard occupied a position on a wooded height overlooking the Red River above the village of Trung Hà, whose plateau, thickly covered in tall umbrella pines, offered an ideal observation post and firing platform for the French artillery.

[citation needed] The Black Flags had thrown up an impressive series of fortifications around Hưng Hóa, but Millot made no attempt to attack the town's formidable defences.

The bombardment began at 10:00 am on 11 April and lasted for several hours, setting many buildings inside Hưng Hóa alight and inflicting heavy casualties on the Black Flag defenders.

The soldiers of the 2nd Brigade spent the day in complete idleness, enjoying the warm spring sunshine and watching the smoke rise silently from Hưng Hóa as the French artillery methodically reduced the town to ruins.

On 11 April, seeing Brière de l'Isle's Turcos and marine infantry emerging behind their flank at Xuân Đồng, the Black Flags evacuated Hưng Hóa before they were trapped inside.

I am happy to say that you have not only added a fair province to our possessions but have once again shown that France has vigorous soldiers animated by the purest kind of patriotism.Given its strategic importance, Millot decided to occupy Hưng Hóa.

The Black Flag Army retreated westwards up the Red River to Thanh Quan, while Prince Hoàng Kế Viêm's Vietnamese forces fell back southwards from Dong Yan towards the Annam-Tonkin border, making for the sanctuary of the province of Thành Hóa, where the French had not yet installed any garrisons.

Millot dispatched Lieutenant-Colonel Letellier with two Turco battalions and supporting cavalry to harry Liu Yongfu's retreat, and sent General Brière de l'Isle with the rest of the 1st Brigade in pursuit of Prince Hoang.

In early May, Brière de l'Isle cornered Prince Hoang in Phú Ngô, several kilometres northwest of Ninh Bình, but the French government forbade him to attack the Vietnamese defences, having just received news that China was ready to treat with France over the future of Tonkin.

It was hoped the Tientsin Accord would resolve the confrontation between France and China in Tonkin, but a clash between French and Chinese troops at Bắc Lè on 23 June 1884 plunged both countries into a fresh crisis.