Hi Carol, I found a good website to start a search. As far as I know, The LS means "landstorm" which I think signifies the type of "assault" which is by land. Landstorm literally means to"storm in" (or come against the enemy)by land.
I am not sure of the following initials, but KNIL means "Koninklijke Nederlands Indish Leger" which in English would translate " Royal Dutch Indonesian Army. The site I found is just a start and perhaps you can elaborate from there: