How does the nature of his errand suddenly shift when he sees the dead man crushed by the elephant?

Initially, the British police officer grabs his .44 Winchester rifle and gets on his pony to search for the elephant when he is given his order to quell the unruly situation. The officer has no intention of harming the elephant and hopes that the sound of his small rifle will scare the massive beast away. Once the officer witnesses the dead Indian man, who had been brutally crushed by the elephant, his errand suddenly becomes more serious, and the intensity of the story begins to rise as the officer requests a more powerful rifle. After witnessing the dead body, the British officer realizes that his mission is potentially dangerous, and he hopes that the elephant gun will protect him if necessary. Even though the officer is holding a more powerful rifle, he has no intention of harming the animal as a crowd of Burmese natives begins to follow him on his errand. After seeing the elephant rifle, the Burmese natives expect the officer to kill the elephant and become excited by the impending action. The crowd increases in size as the officer advances towards the elephant. The peer pressure from the Burmese natives influences him to kill the elephant, which is peacefully grazing by itself.

Once the narrator sees the dead body of an Indian coolie, crushed by a rampaging elephant, he sends his orderly to a friend's house to fetch him a rifle and some cartridges. The military policeman makes it clear that he doesn't intend to use the gun to shoot the elephant. His local knowledge tells him that a working elephant is very valuable to the colonial economy, almost like a piece of machinery. Yet with the rifle slung over his shoulder, the narrator notices a sudden change of mood among the Burmese natives. There's a general air of expectation in the village that the policeman will shoot the elephant. The Burmese see the elephant not as a valuable piece of equipment but as potential meat.
Yet the policeman's still reluctant to open fire. But with a large crowd of expectant villagers surrounding him, he realizes that he has no choice; he has to impress the assembled throng with a show of force, irrespective of his own personal feelings in the matter. Such is the way that colonial power is both established and maintained.