Inspector Grosgurin was a French inspector and commander of a Vietnamese militia in Lao. he had been engaged in several exploratory expeditions in the region. He was a member of one of the French armed columns despatched in April 1893 by de Lassenan to cross the Annamite Range into the Laos area of Khammuan (modern Thakhek) and to occupy the disputed territory. The column was at first successful in evicting the Siamese commissioner at Khammuan by May 25.
Shortly afterwards on June 5, the Siamese commissioner organized a surprise ambush on the village of Kien Ket, where Grosgurin, confined to his sickbed, had encamped with his militia. The commissioner had apparently been instructed by Siamese government representatives to "compel their [French troops] retirement, by fighting, if necessary, to the utmost of their strength" .The ambush resulted in the razing of the village and the killing of Grosgurin and 17 Vietnamese.
The incident and the death of Grosgurin became known as the "Affair of Kham Muon (Kien Chek)" and was ultimately used as a pretext for the strong French intervention