Two seals have been decapitated in Co Kerry, and their severed heads nailed to signs outside the entrance to the Dingle Wildlife and Seal Sanctuary.
The gruesome discovery was made by a passing motorist shortly before 9am.
Gardaí are investigating the incident, and have removed the common and grey seal heads from the scene.
They have also taken away the plaques on which they were hung - which carried the phrases "RIP - cull" and "RIP - I am hungry".
The Dingle Seal Sanctuary says it believes both seals were captured in the wild, and were not among the seals being cared for currently at the sanctuary.
It said the seal heads were mounted on the entrance signs to its carpark on the main road into Dingle overnight.
It said it would not like to speculate on who might be responsible for the incident.
Animal manager at the sanctuary Ally McMillan said the centre had not received any threats in advance. The seals were about six months old.
"Nothing like this has ever happened at the sanctuary before. Nothing to this degree. When we all arrived it was a great shock.
"We were all really sickened by the whole experience. We are still all quite shaken up. It's not a nice thing to come to work and see, especially when we work in a place where we look after these animals," she added.
(Readers are advised that they may find some images disturbing)