Once on the train (according to what the channel said was a leaked police statement, aired Tuesday night) a police officer pinned de Menezes down when another officer shot him.
Menezes got off the train prior to the shooting
( z1 get :ARG1 ( z2 person :name ( z3 name :op "Menezes" ) ) :ARG2 ( z4 off :op ( z5 train ) ) :time ( z6 prior :op ( z7 shoot ) ) )