Wikipedia:

Chasseur [sha-sur; Fr. sha-sœr] (a French term for "hunter") is the designation given to certain regiments of French and Belgian light infantry (Chasseurs à pied) or light cavalry (Chasseurs à cheval) to denote troops trained for rapid action. From its creation as a permanent force in 1832 the Belgian army included regiments of both Chasseurs à pied and Chasseurs à cheval, performing the same roles as their French counterparts. At the outbreak of World War I in August 1914 there were 3 regiments of Chasseurs à pied, each of 3 battalions, and 3 regiments of mounted Chasseurs.[6]

Many of these photos came from the late Roger De Boecke or Fernand Backaert.