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 pilot, 42-year-old Scott Booth and passengers, 29-year-old Ellie Milward, 32-year-old Jonathan Udall and 39-year-old Jennifer Barham were all flown to the University Medical Center in Las Vegas where they're listed in critical condition.
"We are providing support to the families of six British visitors involved in a helicopter accident at the Grand Canyon on February 10, and we are in close contact with the United States emergency services", a Foreign Office spokeswoman said.
Strong winds and rugged terrain prevented survivors from being rescued until Sunday morning.
A still from video footage of the crash's aftermath.
Brenda Halvorson, the CEO of Papillon Group, said: "It is extreme sadness we extend our heartfelt sympathy ot the families involved in this accident".
The National Transportation Safety Board is investigating the cause of the crash.
Teddy Fujimoto, a Las Vegas photographer in the area at the time, said he saw two or three small explosions in the wreckage, and that one injured woman "was pretty much burned all over".
Six passengers and a pilot were on board the Papillion Grand Canyon Helicopters chopper when it crashed under unknown circumstances around 5:20 p.m. Saturday on the Hualapai Nation near Quartermaster Canyon, which is near the Grand Canyon's West Rim and about 60 miles west of Peach Springs. "Our top priority is the care and needs of our passengers and our staff". The aircraft suffered "substantial damage", a spokesman for the Federal Aviation Administration said.
The company says it flies roughly 600,000 passengers a year on Grand Canyon and other tours.
The circumstances surrounding the crash - on the West Rim of the Canyon - are now unknown.