With no explanation, label each line with "location-GPE", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Indiscriminate
firing
by
police
killed
and
injured
hundreds
of
black
African
schoolchildren
during
a
protest
march
.
Indiscriminate:O
firing:O
by:O
police:O
killed:O
and:O
injured:O
hundreds:O
of:O
black:O
African:location-GPE
schoolchildren:O
during:O
a:O
protest:O
march:O
.:O