English Heritage cancels contract over Wrest Park dead deer images
English Heritage said it was "appalled" by images appearing to show hunters posing with deer, apparently killed on one of its estates.
The images from the country estate Wrest Park were shared by Bedfordshire Against Trophy Hunting (BATH).
A woman can be seen resting a gun on a dead muntjac deer in one of them.
English Heritage said it had terminated a working arrangement with an independent specialist "in light of these images".
A spokeswoman for the charity said it was "appalled by these images" from the estate in Silsoe, Bedfordshire.
English Heritage "would never permit trophy hunting" or "hunting for sport" at any of the historic sites in its care, she said.
"However, as part of our responsibility for conservation and caring for the gardens and grounds at Wrest Park, and in accordance with legislation, we do work with an independent specialist to manage the muntjac deer population.
"It's very important to English Heritage that this is done humanely and respectfully and we would never seek to profit from it.
"In light of these images, we have terminated this working arrangement and have launched a full investigation."
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