Thousands of fish have died in a lake in Cheltenham in what the Environment Agency has described as a mass suffocation.
Pittville Lake is part of the town's largest ornamental park.
People are now being warned to stay away from the water.
Katie Rowlett reports:
More top news
Bristol's goes baa-rmy as this summer's Shaun in the City trail kicks off. Plan your quest to find all 70 Shauns with this taster guide.
We've been getting acquainted with the Shaun the Sheep sculptures heading out on location for this summer's trail across Bristol
The Shaun in the City sculpture trail, which hits Bristol's streets on Monday, was given its official, and typically unusual, launch today.