DIJON (AFP)

Children at a primary school in eastern France found a strange new attraction next to their playground this week: a skeleton sitting upright, peeking out the top of a circular pit.

It is just the latest in a series of bodies discovered in the city of Dijon that were mysteriously buried in a seated position while facing west.

Scientists are trying to work out why the ancient and little-understood Gaul people chose to bury some of its dead in this unusual manner, and whether the men were still alive at the time.

The latest skeleton, which is remarkably well-preserved, was found next to the Josephine Baker primary school in the heart of Dijon.

Similar to four others unearthed nearby earlier this month, it is sitting upright at the bottom of a one-metre-wide pit.

The skeleton's hands are resting in its lap. Like the others, its back is against the eastern wall, its gaze directed westward.

Last year, 13 other Gallic skeletons were discovered around 20 metres away at the same construction site. The bodies are believed to date from around 300 to 200 BC.

Over the last three decades, archaeological digs have revealed that Dijon was once a special place for the Gauls, an enigmatic Celtic group of people perhaps best known for the popular French comic "Asterix and Obelix".

The Gauls first emerged in roughly the fifth century BC, spreading over swathes of modern-day France, Belgium, Switzerland and farther east. Little is known about their culture beyond the writings of others. These can be biased, such as what was recorded by the Roman emperor Julius Caesar, who conquered the Gauls in 50 BC.

Including earlier discoveries in 1992, around 20 tombs with sitting Gauls have been discovered in a small area of Dijon's city centre. That is more than a quarter of the 75 tombs featuring sitting Gauls identified worldwide. Other sites have been found in France, Switzerland, and the UK.

Regis Labeaune, a researcher at the French archaeological institute INRAP, said the latest bodies were "particularly impressive discoveries".

"Given the number and quality of these discoveries, we can say there was a significant Gallic settlement in Dijon," he told AFP.

However there is much that remains unknown, especially about the reasons for the unusual positions in which the skeletons were found. Another mystery is whether they were buried alive.

Five of the bodies show signs of violence, including one which has a fatal wound to its skull. Except for one armband which dates the settlement to the Gallic period, no personal belongings or ornaments were found among the Dijon bodies.

There were all men, measuring between 1.62-1.82 metres tall, except for a child discovered in 1992.

Their teeth were very well-preserved over the years, "probably because they did not know about sugar," INRAP archaeo-anthropologist Annamaria Latron said.

"Their bones display traces of osteoarthritis, suggesting intense physical activity," particularly in their legs, she said.

Experts don't yet know why they were buried in the bizarre manner.

"We do not have a preferred hypothesis," Latron emphasised. "We're missing the surface layer, which was above the tombs. Being an archaeologist can be a very frustrating profession," she added with a smile.

The bodies of 28 dogs and five sheep were found near the site in the 1990s. The carcasses appear to date from the late Gallic period and "seem to correspond to sacrificial practices," according to INRAP.

There are still remnants of the Gauls in the modern French language, including the words for country and paganism, INRAP president Dominique Garcia pointed out.

He called for more attention to be paid to the Gauls, given that two-thirds of France's "prefectures have Gallic origins, according to archaeology".