POLICE closed off a building site to investigate the possibility that a human grave had been uncovered after hundreds of bones were unearthed.

Builders at Chiltern Tyres in Dean Street, Marlow, made the grisly discovery on Thursday afternoon. But after a flurry of activity the bones were later found to belong to sheep and pigs.

Paul Glenfield, site manager, said: "We were going about two metres into the ground and the hole we were digging caved in and there was this ribcage poking out of the ground.

"When the bank caved in there were bones absolutely everywhere."

Police were immediately called to the scene.

Mr Glenfield said: "They said it looked like human bones and were waiting for the doctor to turn up which I thought was a bit unnecessary as the man seemed to be well dead. I left the site at 5pm and got a call at 7.30pm to say the site had been closed down. I was told the doctor had sent the bones away for further analysis."

After the results came back police contacted Mr Glenfield to tell him the panic was over.

The site was fully excavated by police to check for any sign of human remains and in all around 300 bones were uncovered.

Mr Glenfield, of Carter Construction in Oxfordshire, added: "It was quite exciting at the time. Not something you come across very often. At first everyone was sure it was human because the rib cages look so similar but I spoke to CID the next day and they explained the difference between the shoulder blades of a human and a pig or sheep so if I found any more bones I needn't call them out."

Mr Glenfield added that they had also unearthed a 30ft dry stone well on the site with 10ft of water at the bottom.

Dr Rachel Brown, Marlow historian, said the discovery of pig and sheep bones was no surprise.

She said: "The remains probably go back to the time that families kept pigs and sheep in their back gardens for food."