Mystery surrounds the death of around 50 badgers, including their cubs, after their sett was bulldozed.

The sett is in the heart of former Occidental refinery land on Canvey, owned by superstore giant Safeway, off the island's Northwick Road.

However, supermarket bosses said they have no idea why there should be a bulldozer on their land. A spokeswoman for Safeway said: "We are very concerned due to the environmental issues involved."

Police are investigating the case, as it is a criminal offence to disturb badgers between December and June when they are breeding and rearing their cubs.

Chief Insp Steve Bottrill, from Rayleigh police, said: "We received a call from a councillor about an incident involving a vehicle and a badger sett and we are investigating."

Wildlife campaigners were horrified at the news. Castle Point councillor Dave Blackwell (Lab, Canvey) said: "It is horrifying to think about what has happened.

"There must have been between 30 and 50 badgers living in that sett. At this time of year it is illegal to go near badger setts because of the young badgers.

"The Occidental land is also an important habitat for rare butterflies and flowers. What has happened is criminal."

Veronica Mepham, of the Rescuers Wildlife Sanctuary in Watlington Road, Benfleet, said: "We have been told nothing could have survived in the sett after the JCB went over it and there would have been cubs inside.

"All the soil would have been squashed inside and would have destroyed all the burrows.

"We believe there was a nest of cubs inside and they all would have died when the area was bulldozed."

The land is also the home of the rare shrill carder bee and the marble white butterfly. These insects are becoming an endangered species and Mr Blackwell was keen to protect the land.

English Nature conservation officer for south Essex, Eric Steer, said: "This is a very important piece of land."

The maximum penalty for destroying a badger sett is six months in prison and/or a fine.

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