DAKAR (Reuters) – A landslide in eastern Democratic Republic of Congo likely killed more than 200 people, based on estimates from the number of households submerged, the vice governor of affected Ituri province said on Friday.

The landslide struck the village of Tora, on the shores of Lake Albert, a seismically active zone in the western Rift Valley, on Thursday.

“There are many people submerged whom we were unable to save,” Pacifique Keta, the vice governor of Ituri province, where Tora lies, told Reuters by telephone. “The rescue is very complicated because there are mountains everywhere, which makes it very difficult to have access.”

Many parts of west and central Africa are vulnerable to landslides, because land is heavily deforested and communities crowd into steep hillsides.

On Friday, Sierra Leone buried 461 victims of a mudslide that swept away homes on the edge of Freetown, the capital, and 600 more people are missing.

Eastern Congo has the added risk of being on a seismic fault line, which means it frequently suffers earthquakes and sometimes volcano eruptions.

Keta said the toll was an estimate based on the number of households submerged and the population of the households. He said that so far about 40 people had been buried.

“We are trying to enhance the emergency response. The aid agencies and MINUSCO (the U.N. peacekeeping force) are there to evacuate bodies and any survivors as quickly as possible,” Keta said.

(This story corrects Keta’s title to vice governor, not governor, in paragraphs 1, 3 and headline)