Three people have been killed and four others are "level one trauma patients" after a helicopter crashed near the Grand Canyon Saturday afternoon, according to Hualapai Nation (Arizona) Police Chief Francis Bradley.
The British Foreign and Commonwealth Office said on Sunday all six were British visitors.
The tour had stopped at Quartermaster Canyon and was on its way back to Las Vegas, where the tour began when the helicopter crashed.
The survivors could not be airlifted out of the canyon until around 2am because of high winds, police said.
National Weather Service meteorologists in Flagstaff and Phoenix said wind conditions were an estimated 10 miles per hour with gusts of 20 miles per hour around the time of the crash.
Rescuers got help from military aircraft from Nellis Air Force Base in Las Vegas and were eventually able to fly all four of the injured to the University Medical Center in Las Vegas by Sunday morning, Bradley said.
Photos of the crash scene showed flames and dark smoke rising from rocky terrain.
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The figures from the two Koreas shared kimchi (Korean pickled cabbage) and soju rice liquor, and spoke for three hours. She is the first member of the Kim family to visit the South since the Korean War.
He said he then heard two or three small explosions where the wreckage was, about 600ft (183m) below from where he was standing.
"The ladies were screaming".
The FAA and the National Transportation Safety Board will investigate.
The aircraft suffered "substantial damage", a spokesman for the Federal Aviation Administration said.
It also says it "abides by flight safety rules and regulations that substantially exceed the regulations required by the Federal Aviation Administration".
The helicopter operator, Papillion Airways, has been involved in at least three other deadly incidents in the past 20 years, says Arizona Republic.
The relationship of those on board was not immediately known, nor what caused the Eurocopter EC130 to crash. "Our top priority is the care and needs of our passengers and our staff", Papillon Group CEO Brenda Halvorson said Sunday.