A warning has been issued after dead fish were found floating in a brook by volunteers responding to concerns about the state of the waterway.

Members of Friends of Brislington Brook said they arrived earlier this week to discover foam on the water and "an intense chemical smell".

Leah Arnold, who helped to clear the Bristol site, said she was "really sad" to see dead eels in the brook, which she had not known were living there.

The Environment Agency said it was investigating the incident and awaiting results of water sampling tests. It is understood the agency is looking into whether there is a link between the incident and a fire which broke out at a derelict warehouse nearby on Tuesday.

Firefighters were once again called to the site of the blaze on Emery Road earlier, following sightings of smoke in the area.

Describing her arrival at the brook earlier in the week, Arnold said she noticed a dead bird and then saw dead eels "everywhere".

"Some were the size of your pinkie, but there were others that were the size of your arm," she said.

The group put out a social media warning to visitors of the brook and alerted the authorities.

Volunteers visited the waterway again on Sunday to carry on the clear-up of the site. They said they had counted more than 30 dead eels so far.

Arnold said she was worried about how the condition of the water could affect locals and their pets - and said she was concerned there were no warning signs in the area.

"Whatever has killed the fish can't be good for dogs or people. I usually let my dog play in the water and she'll have a drink sometimes but I'm not letting her do that now.

"I'm also worried for children who may get sick if they get in the water," she said.

Arnold said the incident felt like a major setback for the group of volunteers.

"Clearing the brook and making the place more biodiverse just feels like a waste now," she added.

Local resident Jessica House said she was walking her dog in the area on Thursday when she noticed bubbles in the water.

"I told the kids and they were really excited because there was foam everywhere and they wanted to give Buddy [her dog] a bubble bath - that did not happen though," she added.

An Environment Agency spokesperson said: "Our officers visited Brislington Brook earlier this week to investigate reports of foam in the watercourse and take water samples.

"We are awaiting sampling results and regularly monitoring the watercourse."

Avon Fire and Rescue Service has been approached for comment.

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