A humanitarian plane went missing during a storm in eastern Democratic Republic of Congo on Monday, U.N. humanitarian coordinator OCHA said, according to Reuters.

"We have a missing plane. We don`t know if it`s landed or crashed," Christophe Illemassene, spokesman in Congo for the U.N. Office for Coordination of Humanitarian Affairs (OCHA) told Reuters.

"We don`t have the manifest so we don`t really know how many people were on board," he said.

The plane was on its way from the city of Kisangani to the town of Bukavu, on Congo`s eastern border with Rwanda, when it lost contact with ground control.

"The last contact that we had was as they were approaching Bukavu ... Apparently the weather was pretty nasty in Bukavu," Illemassene said.

He said the 19-seat Beechcraft was operated by Air Serv International, a not-for-profit organisation which provides air transport services to humanitarian operations around the world.

"We know it didn`t land at any other airport in the area," he said. "There is not really much we can do right now. There will be a search at dawn."

Air Serv is one of several entities and private contractors which service Congo`s large community of humanitarian workers.

Most humanitarian organisations operating in the country restrict travel by their personnel on commercial flights in Congo due to local airlines` abysmal safety record and frequent crashes.