Swans found dead in Stallingborough after chemical spill
Two swans were found dead with another pair coated in an oily substance following a chemical spill.
The spill's source was a discarded 10-litre container found in Middle Drain, Stallingborough, North East Lincolnshire Council said.
The dead birds were discovered on Saturday, with a third bird later spotted in the area covered in what appeared to be oil.
Officials have warned of the dangers of fly-tipping.
Volunteers from Cleethorpes Wildlife Rescue found the first distressed swan in the area last week, prompting a search to find the source of the leak.
They later discovered up to two miles of the Middle Drain watercourse had been contaminated, and spotted another bird in the area covered in what appeared to be oil or diesel.
It is believed it could be paired with the first rescued swan, which is recovering well following a fundraising appeal to pay for its treatment, the wildlife group said.
However, they have so far been unable to catch it.
A spokesperson for the council added: "This incident serves as a reminder of the harm done by fly-tipping and littering."
Follow BBC East Yorkshire and Lincolnshire on Facebook, Twitter, and Instagram. Send your story ideas to [email protected].