Health officials found 30 dead swans in the River Thames over the the space of a week, as fears grow of a new bird flu outbreak in the UK.
The Department for Environment, Food & Rural Affairs (DEFRA) recovered the bodies and is carrying out tests to determine the cause of death.
Sky News understands that the incidents have been reported around the inner and outer Millwall Docklands near Canary Wharf in east London over the past week.
Canal & River Trust ecologist Ben Macmillan told Sky News that a specialist contractor "collected 30 dead birds, all swans, from our waterways in and around West India and Millwall Dock".
There is no risk to the general public, but Mr Macmillan said that to limit the potential spread of what he called a "suspected avian flu outbreak", members of the public should not touch any dead birds they find and report them to DEFRA.
According to the NHS, avian flu is an infection that mainly affects birds, but can spread to humans through close contact and can be fatal.
The Royal Society for the Protection of Birds added that there are several strains of avian flu, most of which cause no symptoms in birds.
A 2021 outbreak of the disease, however, saw thousands of farming birds culled.
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An Animal and Plant Health Agency spokesperson said: "We are aware of a number of swan deaths around West India and Millwall docks, and are investigating this as part of APHA's dead wild bird surveillance scheme.
"Members of the public are advised to not touch or pick up any dead or visibly sick birds that they find and should wash their hands thoroughly with soap and water if they touch wild bird faeces or feathers or after feeding wild birds."
(c) Sky News 2026: Thirty dead swans found amid 'suspected avian flu outbreak'
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