The accident took place at around 5.20pm in Grand Canyon West, northwestern Arizona, said Hualapai Nation police chief Francis Bradley.
Three passengers were confirmed dead.
He said that's when two or three small explosions went off in the wreckage and people weren't sure what to do.
He said winds up to 50 miles per hour and rugged conditions near the crash site were making it hard for rescue crews to reach the victims.
Bradley says National Transportation Safety Board officials were expected at the crash scene by Sunday afternoon to begin investigating the cause of the crash.
The Federal Aviation Authority's spokesman has explained the helicopter to have undergone "substantial damage". As of Sunday morning, the aerial sightseeing company that owns the helicopter hadn't released a statement.
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Hutchison's swimming club, the King Aquatic Club in Washington state, said in a statement the news "broke our collective hearts". They also said USA Swimming knew eight years ago that Hutchison "was involved in an inappropriate coach-athlete relationship".
"Quartermaster Canyon is an extremely remote area".
Calls to Papillon's media representatives were not immediately returned Saturday.
The Arizona Department of Public Safety said the organization was assisting the National Park Service with the crash.
Las Vegas photographer Teddy Fujimoto was shooting wedding photos at the time of Saturday's crash when he saw people running to the edge of a gulch. Every year, it ferries some 600,000 people on helicopter and other tours.
Papillon's helicopter tours have landing zones on Hualapai lands. It started operating out of Boulder City Airport in 2004 and opened a 45,000-square-foot base there in 2009.