Hualapai Nation Police Chief Francis Bradley says navigating the rugged terrain in the dark made it hard for first-responders to reach the helicopter's wreckage.
Three further Britons - named by police as Ellie Milward, 29, Jonathan Udall, 32, and Jennifer Barham, 39 - were airlifted to University Medical Centre in Las Vegas, Nevada, along with pilot Scott Booth, 42.
A pilot and six passengers were on board, Bradley said.
Hualapai Nation Police Chief Francis Bradley says the survivors all were taken to a Las Vegas hospital as of 2 a.m. Sunday.
Strong winds and rugged terrain prevented survivors from being rescued until Sunday morning.
"Yesterday, we were hampered by severe weather conditions, we had gusts up to 50mph".
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Kane , 24, has continued to star this season, scoring 22 Premier League goals to take his tally to 100 overall in the competition. We missed opportunities on counter-attacks that are not missable at our level.
"The ladies were screaming".
The FAA and the National Transportation Safety Board will investigate, Kenitzer said.
Allen Kenitzer with the FAA Office of Communications confirmed in an email that the helicopter, a Eurocopter EC130, "crashed under unknown circumstances in the Grand Canyon".
Papillon Grand Canyon Helicopters, run by Papillon Airways, prides itself as being "the world's largest aerial sightseeing company" and "the only way to tour the Grand Canyon". It also notes that it "abides by flight safety rules and regulations that substantially exceed the regulations required by the Federal Aviation Administration".
Federal authorities continue to investigate a deadly helicopter crash in the Grand Canyon. "Our top priority is the care and needs of our passengers and our staff", Papillon Group CEO Brenda Halvorson said Sunday. The pilot, who survived the accident, suffered injuries to at least "one of his limbs", officials said.
NTSB investigators determined the probable cause of the 2001 crash was pilot error.