MYSTERY surrounds a 12ft hole discovered under a historic part of a Suffolk market town.

Curious onlookers peered into the large cavern which emerged under Woolhall Street in Bury St Edmunds yesterday.

Anglian Water workers discovered the void while repairing a mains leak on Tuesday night.

The road was closed while the depths of the chamber were explored.

A spokeswoman for the firm said: “We were called to repair a burst and, as we were doing excavations, we discovered a void under the road.

“We thought this may be an old, underground tunnel.”

Some believe the cave was part of a network of secret tunnels used by medieval monks to travel from the town’s abbey.

But Bury historian Clive Paine said there were no tunnels in the town.

“There is a prevailing folk myth that Bury is filled with tunnels that were used by monks to get from one place to another,” he said.

Colin Pendleton, a historic environment officer, believes the deep pit could be linked to a series of chalk mines worked in the town in the medieval period.

Mr Pendleton, who works for Suffolk County Council’s archaeological service, said a large, 25ft shaft was discovered in the 1970s while work to build what is now Betfred on the corner of Woolhall Street took place.

In 1967, a 25ft crater appeared under a house in Jacqueline Close in Bury, when old chalk mine collapsed.

But the true origins of the void in Woolhall Street will now never be known as the hole has been filled with cement.

A spokeswoman for St Edmundsbury Borough Council said the road could remain closed for at least the next few days.