A mysterious previously unrecorded burial chamber has been discovered hidden beneath a medieval village churchyard near Ashwell.

Letchworth’s Brian Munnery found the lost brick chamber by accident while clearing overgrown plants in the graveyard at St Mary Magdalene’s Church in Caldecote – the smallest village in Hertfordshire, with a population of just 19.

“Removing the roots, a bit came out that was so big I had to drag it away,” said Brian, a member of the Caldecote Church Friends committee that cares for the now rarely-used site.

“I pulled it away and there was this tidy little hole, and this brickwork. I put a stick down to determine how deep it was.

“I called the landowner, and he said it was just a drain. When we got in there with the infrared camera, though, it soon became clear that wasn’t the case.”

The 8ft-long tomb appears to contain bones and two lead coffins, and the Caldecote Church Friends are now working to try and clear up the mystery of who built it and who is buried within.

“We haven’t been able to find any reference to this chamber anywhere in the church records,” said Brian.

“Most of the graves here come from two families, the Flints and the Inskips, which intermarried. But nobody we’ve spoken to had any idea that this was here.”

Brian has dated the chamber to the late 18th or early 19th centuries, based on the style of brickwork and the fact that neighbouring graves date from 1798 and 1801.

The Caldecote Church Friends have closed it up again for the time being while they await advice from experts further afield.

Archaeological excavations at Caldecote between 1973 and 1977 revealed artefacts from the Bronze and Iron ages, but did not uncover this tomb.

Brian said: “The history of this place is just amazing. You can put your hand down on the original pews from the 14th century, and just think of all who have come before.

“We just hope others will be able to shed some light to help us solve this mystery.”

St Mary Magdalene’s Church, a grade II*-listed building, was declared ‘redundant’ in 1974 – meaning it is no longer used for regular public worship.

It was invested in the Friends of Friendless Churches charity in 1982, and now hosts a single religious service annually – usually to mark the patronal feast of St Mary Magdalene, which falls on July 22.

Caldecote Church Friends was set up in 2007 to support the charity in maintaining the church.

If you think you can help them solve the mystery, call their secretary Mathew Jones on 07949 214354 or see caldecotechurchfriends.org.uk.