A missing helicopter belonging to the U.S. Marine Corps, conducting relief work in the earthquake-affected region of Nepal, may have gone down in a river in the Charikot area, about 81 miles from the capital Kathmandu.

There were six U.S. Marines and two Nepalese soldiers on board the chopper. They were reportedly heard talking about fuel problems before the radio contact was lost with the crew.

"The info we have is that it is down in one of the rivers, but none of the choppers has seen it yet," Major Rajan Dahal, second-in-command of the Barda Bahadur Batallion, said, according to ABC News, adding: "There are 400-plus of our ground troops looking for it also, by this evening, we might get it."

The helicopter was working in Charikot, which was one of the hardest-hit villages by the 7.3-magnitude earthquake on Tuesday that has killed at least 65 people and injured nearly 2,000 so far. The region was also devastated after last month’s tremors that measured 7.8 magnitude and killed over 8,000 people in the country.

An initial air search for the helicopter on Tuesday had reportedly failed to locate the plane. Ground forces from Nepal were sent to look for the people on board, Reuters reported. Two helicopters from the aircraft set -- of which the missing chopper was a part -- were also sent to conduct an aerial search.

Many Nepalis were forced to stay in makeshift tents and relief camps following Tuesday's quake and subsequent aftershocks.

"Even those houses that have not been flattened have developed cracks. People are too afraid to go into them," Aula Bahadur Ale, assistant administrator of Dolakha district, said, according to Reuters, adding: "It looks like a graveyard here. We are still feeling the aftershocks that make people terrified." Charikot is the district capital of Dolakha.