Rio De Janeiro - Some 150 police officers from the northern Brazilian state of Para went on trial yesterday for the deaths of 19 landless peasants who were killed during a protest in 1996. Some 2,500 peasants on April 17th, 1996, had occupied land near Eldorado dos Carajas, in the southern part of the state, and were blocking a road calling for land reforms. Police were sent to clear the road but when the peasants began throwing stones they fired machine-guns into the crowd.