Mayhem in Nigeria , the fifth-largest oil supplier to the United States and Africa 's most populous country , is escalating .
Africa /location/location/contains Nigeria
NNP IN NNP , DT JJ NN NN TO DT NNP NNPS CC NNP POS RBS JJ NN , VBZ VBG .
Africa
LOCATION
Nigeria
LOCATION
/location/location/contains