Around 80 percent of those who died in the town of Atsuma after Thursday's powerful Hokkaido earthquake died of suffocation, investigative sources said Tuesday.

Most of the 36 victims — 20 men and 16 women — were elderly and were found near their homes, apparently having been buried alive as mud from massive landslides engulfed their homes in the early hours of Thursday. The other 20 percent died of traumatic injury as the landslides also destroyed and pushed homes toward nearby roads and farmlands.

A woman in her 60s who was on the second floor of her home when a landslide struck said, "The first floor was smashed right after the earthquake and the second floor was pushed out about 30 meters. I could not save my mother-in-law who was sleeping downstairs."