An amphibious plane carrying former senator Ted Stevens crashed into a remote mountainside in Alaska on Monday. (Alaska State Police/Associated Press)

Rescuers described the grim scene of wreckage, bodies and survivors from the site of the plane crash that killed Ted Stevens, a former U.S. senator from Alaska, and four other people.

The single-engine float plane smashed into a mountain in Alaska on Monday with nine people on board. Four people survived, including ex-NASA chief Sean O'Keefe, 54, and his teenaged son, who spent 12 hours overnight waiting to be rescued.

A doctor and an emergency medical crew were flown to the area and hiked to the wreckage as nightfall set in. But bad weather prevented the National Guard from getting to the crash site until Tuesday.

Three of the four survivors along with the bodies of those killed in the crash remained in the fuselage of the aircraft, which was still intact.

A pilot who was one of the first to arrive at the scene described seeing a survivor still strapped in the front seat with the nose of the plane disintegrated. The passenger's head was cut, and his legs appeared to be broken.

"The front of the aircraft was gone," Ted Tucker said. "He was just sitting in the chair."

Tucker and the other responders made a tarp tent over the missing cockpit to keep him dry. It was rainy and cold.

"These individuals were cold. We covered them up with blankets and made them as comfortable as we could," he said.

Medical workers spent the night tending to survivors' broken bones.

A 13-year-old boy, whose father did not survive, was reportedly huddled under a wing trying to stay dry.

"As we approached the aircraft, you could smell the fuel, the wings were swept back, the engine compartment of the plane had broken off or buried itself into the ground," said Master Sgt. Jonathan Davis, who was among one of the first National Guardsmen to reach the site.

Davis said survivors inside used fishing waders to keep warm.

"Those fishing waders keep the wet out and keep the heat in, acting pretty much like a survival blanket and so yeah, I would say that definitely helped them out," he said.

The nine people aboard the plane were headed to a remote fishing camp when the plane went down in rain and fog.

It skidded up a steep hill before coming to rest in a wooded ravine near Dillingham in the southwest corner of Alaska.

The pilot, a woman and her teenage daughter, as well as a Washington lobbyist and Stevens were all killed.

Technical Sgt. Kristopher Abel said it was a challenge moving everyone from the remote crash site.

"It was actually pretty labour-intensive because of the angle of the slope and the inside of the aircraft was quite slippery. And we had to cut a large hole in the side of it in order to get the people on litters out. So it was quite time-intensive and labour-intensive."

Greg Feith, who used to be an investigator with the National Transportation Safety Board, said he wants to know why the pilot took off in such bad weather.

"The mountain that they hit probably was shrouded in very low clouds, mist, fog, rain and he may have been trying to just, what we call scudrun or stay below the bottom of the cloud, and may not have actually seen where he hit."

With files from The Associated Press