Emergency and environmental crews were called to the Pequabuck River in Bristol on Tuesday, after oil was spotted in the river.
Police said they received a call about oil having been found in the river on Tuesday evening.
The Department of Energy and Environmental Protection was called to the scene, and said they found "red dyed #2 fuel oil" in a catch basin network that is impacting the river.
It is coming from an unknown source, DEEP crews said.
"An environmental clean-up company placed a boom in the basins and vacuumed out recoverable product in an effort to identify the infiltration point. DEEP ETU staff will work with the property owners to attempt to identify the source," officials from DEEP said.
It is unclear exactly where in the river this is happening.
Stay updated with Eyewitness News as more information becomes available.
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