Indigenous tribesmen deep in the world's largest rainforest have found at least nine survivors after a Brazilian military transport plane crash-landed in a river in the Amazon, the air force said on Friday.
One person on the flight that went down on Thursday in far northwestern Brazil was found trapped in the plane and is presumed dead, while another went searching for help and is missing, the air force said.
Members of the Matis, a tiny tribe of some 300 people first contacted by modern Brazilian officials in the 1970s, discovered the plane and its crew and passengers "in the middle of the Amazon jungle" between the Matis village of Aurelio and another tribe's village, the air force said in a statement.
The C-98 Caravan, a single-propeller Cessna transport plane, lost radio contact Thursday 58 minutes into its flight from Cruzeiro do Sul, in northwestern Acre state, to the Amazonas town of Tabatinga, where the borders of Brazil, Colombia and Peru come together.
The plane apparently crash-landed on the Itui river, a small tributary of the Amazon near the Peruvian border, and it was the pluck of the pilot that saved the lives of his passengers, according to a survivor.
"We are happy to be alive," he told local indigenous health official Jose Francisco Correa de Araujo, according to news website UOL.
"The engine of the plane stopped, and we panicked, but the pilot managed to land the aircraft on the river."
Air force officials said the plane now lies submerged in five meters (16 feet) of water.
The survivors were transported by helicopter back to Cruzeiro do Sul, and "they are doing well," the air force said.
The Globo news network reported that six of the survivors were taken to the city's main hospital, where clinical director Fabio Pimentel said none had suffered serious injuries.
Four crew members and seven passengers -- two women and five men, all health ministry employees -- were aboard the plane when it went down.
The passengers were undertaking an immunization campaign in indigenous communities, a spokesman for the National Health Foundation (FUNASA) in Cruzeiro do Sul told AFP.
The missing person was a member of the military crew who went searching for help, a FUNASA spokesman told AFP on Friday. Matis villagers were assisting in the search for the crew member as well as the ministry employee believed to have been killed in the crash, the air force said.
Aviation expert Gustavo Cunha Mello told Globo that the C-98 Caravan is a slow-flying aircraft built in a way that would likely allow passengers and crew to survive if there was an emergency landing.
Eight aircraft had been scouring the rainforest, but the improbable rescue in one of the world's most remote regions is credited to the Matis.
They "heard a different sound while hunting in the dense jungle," Brazil's National Indian Foundation (FUNAI) said in a statement on its website.
"In seeking the source of the noises they found the Brazilian Air Force aircraft" in a riverbed about a two-hour walk from their village, it added.
They used a radio to contact FUNAI officials, who gave the military the exact coordinates of the village.
The region is home to several isolated tribes, including some which have never had contact with the outside world.
Just days before the plane crash, according to indigenous rights protection group Survival International, FUNAI announced it would launch an expedition in November to search for uncontacted tribes in the Javari valley, where the Matis live.
"FUNAI thinks that more uncontacted indigenous groups could be living in this densely forested area than anywhere else in Brazil," Survival International said in a report.
Last year, FUNAI released dramatic images of a tribe -- living a few hundred kilometers south of Thursday's crash site -- believed never to have had contact with the outside world.
Brazil's indigenous population was decimated by the arrival of Portuguese settlers in the 16th century.
According to FUNAI, their number has plunged from as many as 10 million to just 460,000 today -- a tiny fraction of the 190 million people who now live in the country.