More than 60 swans have been rescued from a Berkshire river polluted by oil.
All 60 swans are expected to make a full recovery
The birds were picked up from the River Kennet in Reading by experts from Swan Lifeline and taken to the charity's treatment centre in Eton.
Kay Webb, chair of the charity, said the spillage appeared to be cooking oil and the swans were being cleaned with washing-up liquid.
The Environment Agency has secured the polluted area at Blake's Lock and is investigating the incident.
Ms Webb told the BBC that all the swans were expected to make a full recovery.
She said: "It will take a bit of doing cleaning them up, but we'll sort them out.
"The problem is if they ingest the oil while cleaning themselves - that can make them really sick."
A spokeswoman for the Environment Agency said an investigation into the source of the spillage and the type of oil was under way.
She said the area had been secured with booms and all the swans had been taken off the water.
No other wildlife is thought to have been affected.