Dead carp

Observation - Dead carp - UK and Ireland. Description: The pond in my garden is about 1000 square metres. We have lived there 4 years and each Spring we see 5 large carp as they appear at the surface when the water warms up. This year we have 2 dead ones. The picture shows the size - about 45 cms long and wei

The pond in my garden is about 1000 square metres. We have lived there 4 years and each Spring we see 5 large carp as they appear at the surface when the water warms up. This year we have 2 dead ones. The picture shows the size - about 45 cms long and weighing 4 to 5 kilograms. But this is the position we found it in. Something has attacked it and pulled it out of the water, but only partially eaten it. Has anyone any ideas as to what animal might have attacked it. The pond is in a domestic garden on the outskirts of Worcester