What is the ruling when an animal of unknown status dies in water?

Chapter on what purification is achieved with regarding water

Al-Mughni

Book of Purification

Book 2 · Issue 8 · Bab 2

Open in Qurani

Primary text

If an animal of unknown status dies in the water, the water remains pure because the original state is purity, and impurity is only a matter of doubt; certainty is not abandoned for doubt. The same ruling applies if an animal whose residual drink (su'r) is questionable in purity drinks from the water.