Archaeologists have unearthed remains of 97 human bodies stuffed into a 5,000 year-old small house, possibly killed in an epidemic of some sort, in northeast China.

The bodies of juveniles, young and middle-age adults were packed together in the house - smaller than a modern-day squash court - before it burnt down.

A "pre-historic disaster," possibly an epidemic of some sort, killed these people, researchers said.

The site dates back to a time before writing was used in the area, when people lived in relatively small settlements, growing crops and hunting for food, 'Live Science' reported.

"Hamin Mangha site is the largest and best-preserved pre-historic settlement site found to date in northeast China," researchers wrote in the journal Chinese Archaeology.

In 2011, researchers unearthed the foundations of 29 houses, most of which are simple one-room structures containing a hearth and doorway.

The house with the bodies, dubbed "F40," was nearly 20 square meters.

"On the floor, numerous human skeletons are disorderly scattered," researchers said.

"The skeletons in the northwest are relatively complete, while those in the east often [have] only skulls, with limb bones scarcely remaining," they said.

Fire likely caused wooden beams of the roof to collapse, leaving parts of skulls and limb bones not only charred but also deformed in some way, the report said.

Researchers at the Jilin University in China have found that about half of the individuals were between 19 and 35 of age. No remains of older adults were found.