A minor oil spill in the River Avon at Pewsey on Saturday is being investigated by Wiltshire Council.
It is believed that the substance is heating oil which is causing a sheen on the water in the centre of the village.
The Environment Agency is providing support to the council during the investigation.
Paul Gainey, of the Environment Agency, said: “We deployed a boom to recover some of the oil.
“Quite a few people have noticed it but it looks worse than it is. There are no reports of dead fish.
“We’ll continue to monitor the river and replace the boom as and when necessary.”
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here