The incident happened on Monday evening in Na Quan Village, Nam Hoa Commune.
The scene of the incident
The victims were a local 47-year-old man and his two relatives, one aged 30 and the other aged 41 from Bac Giang Province who came to visit him.
The house is located behind a high hill. When the landslide happened, soil and mud from the hill engulfed the house.
Two other people in the house escaped.
Local authorities sent nearly 100 people to the site. The bodies of three victims have been found.
Many northern localities, including Thai Nguyen, have been facing heavy rains.