Hundreds of fish dead after sluice gates opened at Harthill Reservoir near Sheffield

• Report by Martin Fisher.

A police investigation has been launched after hundreds of valuable fish died when sluice gates were opened at a reservoir.

The fish, including carp worth hundreds of pounds, were let out from Harthill Reservoir near Sheffield.

Anglers attempted to rescue the stricken animals, but it is suspected that hundreds died or were badly injured when they ended up in the adjacent shallow brook.

Ben Elliott managed to save 11 carp, including some which were over 30 years-old.

He told ITV News: "Some of these fish are a lot older than I am and people in the local community.

"These fish have been here way before them."

He added: "The brook was nothing like what they were used to. Full of rocks, too shallow, oxygen levels were low.

"A lot of them were destroyed. Even the ones that were alive had fins missing, scales ripped off - just absolutely destroyed."

Sluice gates are used to control water levels in waterways. It is not known who was responsible for the incident at Harthill, or how many fish died as more continue to surface.

South Yorkshire Police has launched an investigation under the Animal Welfare Act 2006.

A spokesperson said that the fish had experienced "unnecessary suffering".

They added: "We want to hear from anyone who may have been at the reservoir this week in order to establish how this happened. The team are also in talks with the Canal and River Trust who control the reservoir."

Kristian Kent, from the Angling Trust, said: "Often people don't consider fish to be comparable with other animals.

"I think fish are invisible to most people because they're below water, but certainly if this was a kill of mammals there would be more public uproar."

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