Three British people have died after a tourist helicopter crashed in the Grand Canyon in the US state of Arizona.
The Foreign Office said it was providing support to their families and those of three more Britons who were injured.
The aircraft came down at about 17:20 local time (00:20 GMT) on Saturday. It is not clear what caused the crash.
A spokesman for the Federal Aviation Administration said it suffered “substantial damage”.
Police Chief Francis Bradley, of the surrounding Hualapai Indian reservation, told the BBC that all six people involved in the crash were from the UK.
He earlier told US media that the local terrain had hampered rescue efforts overnight.
“We are having difficulties getting the four people out of the crash site area to the hospital,” CNN quoted him as saying.
“It is too windy and it’s dark and the area is very rugged.”
A Foreign Office spokesperson said: “We are providing support to the families of six British visitors involved in a helicopter accident at the Grand Canyon on 10 February, and we are in close contact with the US emergency services.”
The helicopter was operated by tour company Papillon Airways.
On its website, Papillon calls itself “the world’s largest aerial sightseeing company” and says it flies more than 600,000 people a year.
Images have emerged showing flames and thick smoke rising from the boulder-strewn crash site.
Earlier reports said the helicopter was carrying six passengers and the pilot.
The Grand Canyon, which is more than 1.6km (one mile) deep, is one of the most visited tourist attractions in the US.