An investigation into an Anglo-Saxon settlement is to be reopened after it was found to contain rare artefacts.

Archaoelogists found the remains of a wooden tower from the 9th Century at the site in Bishopstone, near Shoreham.

There was also a skeleton with a hole cut through a leg bone, implying people living there may have been using pioneering surgical techniques.

Excavations have been carried out every summer for the last three years, led by Gabor Thomas of the University of Kent. He will open a new dig in August.

Dr Thomas said: "Last summer produced some fantastic results. On that basis we have decided to go back for a final year."

The settlement is easier to excavate than many rural Anglo-Saxon settlements because it was temporarily abandoned then rebuilt in a different location.

Often evidence of Anglo-Saxon structures is hidden because buildings from later periods have sprung up on the same sites.

It is believed the tower in Bishopstone may have been part of the residence of an important dignitary.

Dr Thomas said: "If we find buildings, we are always trying to understand if are we dealing with the equivalent of a modern suburban estate or something more special. This structure was a status symbol."

The skeleton was found in a cemetery area and the person appeared to have died from the unusual injury.

Dr Thomas said: "There was a perfectly cut hole going straight through the bone just above the knee. It is perfectly rectangular, almost as if it has been carefully cut in a surgical procedure. I have never seen anything like that."

The dig will run from August 8 to September 16 and will be carried out by members of the University of Kent, the Institute of Archeology, London and Sussex Archaeological Society.

Volunteers are also needed. Places cost £180 for a five-day training course, from 9am to 5.30pm.

For details, write to Alison Lawrence, Barbican House, 169 High Street, Lewes, East Sussex, BN7 1YE, call 01273 405730, e-mail castle@sussexpast.co.uk or visit www.sussexpast.co.uk