REMAINS of another 14 bodies buried in a mysterious mass grave near Durham Cathedral have been discovered by archaeologists.

A team from Durham University revealed last week that they had found four bodies in a burial pit during building work at Palace Green Library.

Now preliminary excavations of the site in the shadow of the cathedral have seen the total rise to 18.

Experts say the centuries-old mass grave appears to be unusual, with evidence that the corpses were tipped into the ground rather than being respectfully buried.

When the first remains were unearthed in November, it was believed that they came from the cathedral’s medieval cemetery and was taken as evidence that the graveyard’s boundaries may have extended further than the present day burial site.

But further investigation has revealed an unorthodox layout to the bodies which archaeologists say is proof of a mass burial.

Richard Annis, senior archaeologist with Durham University, said: "We have found clear evidence of a mass burial and not a normal group of graves.

"One of the densest areas of the excavation was further north, which is further away from the edge of the presumed graveyard.

"The bodies have been tipped into the earth without elaborate ceremony and they are tightly packed together and jumbled.

"Some are buried in a North to South alignment, rather than the traditional East to West alignment that we would expect from a conventional medieval burial site."

The team plan carry out further research into the remains, including dating the bones and looking for clues as to their origin, in the New Year.

Mr Annis added: "The process of post-excavation processing, examination and analysis is essential to allow us to draw proper conclusions about this group of human remains.

"It is too early to say what they may be."

The archaeologists have been given permission from the Ministry of Justice to carry out excavation works on the World Heritage Site before taking the bones away for further examination.

By law, the bones must eventually be reinterred at an approved burial ground.