A scientist researches at Na Mo Cave.

BAC KAN (VNS)— Six corpses, dating to 6,000 years ago, have been unearthed in a cave in Ngan Son District of northern Bac Kan Province, according to scientists from the Viet Nam Archaeology Institute.

The partially-destroyed skeletons were found at a depth of 1.2m, within a 15sq.m excavation area in Na Mo Cave.

"We haven't found any traces of skulls or teeth from the corpses," Trinh Nang Chung, head of the excavation team, told Viet Nam News. "We guessed the skeletons may involve an old custom of head hunting, popular in Southeast Asia in early history."

Hundreds of objects, including stone working tools, ceramic wares and even samples of flower pollen, have been unearthed at the site.

Chung said the cave had been a home to generations of primitive humans, who lived in two periods, 6,000-7,000 years ago and 3,500-4,000 years ago, it was determined, based upon the two cultural layers found at the site.

Research is to continue at the site. — VNS