HANOI, Vietnam (AP) — A disaster official says seven people have been reported missing and feared dead in a landslide that happened during sunny weather in northern Vietnam.

Pham Quoc Hung says more than 100 soldiers have been mobilized to search for the victims, including two children who were buried under up to 30 feet (10 meters) of earth and rocks following the landslide Sunday in Yen Bai province.

The victims were harvesting corn when the landslide occurred on a sunny day, Hung said Monday, adding that there were slight rains in the area during previous days.

Authorities still don't know the cause of the landslide, he said.