Sita Air, crashed minutes after take-off from Nepal's capital, Kathmandu, around 06:19 local (06:02IST 00:32Z). All 19 people on board, 13 foreign tourist, three Nepali passengers, and three crew, are feared dead.
The plane was on its way to Lukla, a popular hub for trekking in the Everest region.
Police spokesman Binod Singh told AFP news agency
"The pilots seem to have tried to land it safely on the banks of the river but unfortunately the plane caught fire,"See photo of the crash at Nepali Blogger site.
Nepal does not have a large road network and the country's domestic airlines which most operate small turbo-props, provide critical linkage to numerous "airports" within the country, most of these airports in remote areas, are just basic airstrips.
This is the sixth fatal crash in Nepal, in less than two years.