More than 4,000 people were living in the area affected by the large landslide that flattened villages in Papua New Guinea’s Enga province, according to aid group CARE Australia.

Hundreds of people are feared dead in the landslide that hit the Kaokalam community, about 600km northwest of the capital Port Moresby, at around 3am on Friday (local time).

According to Australia’s Department of Foreign Affairs and Trade, at least six villages were affected by the landslide. The Post Courier newspaper in Papua New Guinea reports that more than 300 people and 1,182 houses were buried in the mud.

Australian television reports that the search and rescue operation continues under adverse conditions, as the affected area is only accessible by helicopter as roads are blocked. At the same time, fears are expressed about the risk of new landslides. “Many more homes could be at risk” if landslides continue, a CARE Australia spokesman warned.

The humanitarian aid organization points out that many people displaced by ethnic conflicts had taken refuge in the affected area.

In February, 26 people were killed in an ambush in Enga province, where rising tribal violence prompted Prime Minister James Marape to give the military expanded powers to restore law and order.