A spokesman later told CNN in an email that four people were injured in addition to being killed. On Sunday, the park service released a statement identifying the man killed as 67-year-old Ronald Vanderlugt. Vanerlugt was on the fifth day of his trip on a commercial motorboat on the river when he went into the water, he said. “Team members pulled him out of the water, found him unresponsive and began CPR. Rangers flew to the site in the park’s helicopter and all resuscitation efforts were unsuccessful,” the park service said. “Four other patients in non-critical condition were treated and transported to the South Rim Helibase,” the statement said. “The incident is under investigation by the National Park Service and the Coconino County Coroner.” A rafting company that runs Grand Canyon expeditions describes Bedrock Rapids on its website as a place where a large rock divides the current of the Colorado River. “The best run is on the right side, which requires expert and precise handling to bring a boat around the rock and into calm water. The left side is an unforgiving place as the river pinballs through a narrow channel with rock,” rafting company Western River Expeditions Says. CNN’s Susannah Cullinane contributed to this report.