Around 15,000 fish have been released into a Norfolk river following a "pollution incident" three years ago.
The fish, consisting of 5,000 chub, 5,000 dace and 5,000 roach, were released into the River Thet.
The Environment Agency (EA) said the restocking comes as part of a recovery plan following a pollution incident 2018.
Fisheries officers released the one and two-year-old fish, which had been bred at the Environment Agency's Calverton fish farm in Nottinghamshire.
Kye Jerrom, a fisheries specialist for the EA, said: "The purpose of fish stocking is to enhance and develop our rivers.
"Our aim is to create a river that can manage natural predators and support angling.
"Every penny made from fishing licence income is spent on making improvements to rivers to benefit anglers."
1,000 crucian carp were also distributed between two fisheries in Norfolk and Buckinghamshire, said the agency.
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