Investigations are continuing into what may have caused an oil spill which led to around 150 swans having to be rescued from the River Thames between Windsor Bridge and Eton Bridge over the weekend.
The Environment Agency has said the mystery substance could have been caused by illegal flytipping, leakage from boats or tanks, or faulty drainage.
It is hoped that the birds, which are being cared for by charity Swan Lifeline, can be released on Tuesday.
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Sunny this evening, then dry overnight. There is the risk of thundery showers for Kent tomorrow morning, then sunny spells by the afternoon
Sunshine to end the day then dry tonight. Tomorrow will be mostly dry and feeling fresher with the risk of a heavy shower in the afternoon
The video, obtained by ITV News, shows scores of migrants desperately trying to board lorries in a restricted area within the tunnel.