Rescuers in fishing boats pulled bodies from the muddy Mekong River on Thursday as officials in Laos ruled out finding survivors from a plane that crashed in stormy weather, killing 49 people, including one Canadian.

Backpacks, an airplane propeller and passports were among the debris scattered on the riverbank where the Lao Airlines turboprop plane apparently hit hard before skidding into the water and sinking Wednesday.

"So far eight bodies have been found. We don't yet know their nationalities," said Yakao Lopangkao director general of Lao's Department of Civil Aviation, who was at the crash site in Pakse, in southern Laos.

"We haven't found the plane yet. It is underwater. We're trying to use divers to locate it."

He ruled out any chance of finding survivors. "There is no hope. The plane appears to have crashed very hard before entering the water."

Some bodies were found as far as 20 kilometres from the crash site, he said.

"We have asked villagers and people who live along the river to look for bodies and alert authorities when they see anything," he said.

Crash cause unclear

Fleets of small fishing boats and inflatable rafts plied the muddy, vast waterway as part of the search with men in life vests peering into the water. After storms Wednesday, the search took place under sunny blue skies.

Thailand, which borders southern Laos, was helping with the search. It sent 30 scuba divers to assist in the search for bodies, said Thai Foreign Ministry spokesman Sek Wannamethee.

Pakse, Laos

Thai Foreign Ministry spokesman Sek Wannamethee said the flight crashed about 8 kilometres short of the international airport at Pakse. (Google)

Details of the crash remained murky. The state-run Lao Airlines said in a statement that the plane took off from the capital Vientiane and "ran into extreme bad weather conditions" as it prepared to land at Pakse Airport.

The airline said it had yet to determine reasons for the crash of the ATR-72 aircraft which was virtually new and had just been delivered in March. The crash occurred about seven kilometres from the airport.

French planemaker ATR said in a statement that "the circumstances of the accident are still being determined." It said that it will assist in the investigation which will be led by Lao authorities.

A passenger manifest faxed by the airline listed 44 people: 17 Lao, seven French, five Australians, five Thais, three Koreans, two Vietnamese and one person each from Canada, China, Malaysia, Taiwan and the United States. Korean, French and Thai officials confirmed the totals for their nationalities.

A Foreign Affairs spokesman in Ottawa said the department was working closely with local authorities to confirm if Canadian citizens had been affected.

Australia's Department of Foreign Affairs and Trade said six Australians were on board. Relatives released a photo of a family, Gavin and Phoumalaysy Rhodes and their two children, a three-year-old and a 17-month-old. The passenger manifest identified the three-year-old as Lao, and the discrepancy wasn't immediately reconciled.

The other two Australians were an aid worker based in Laos and his father, who was a retired teacher.

With files from the Canadian Press