Footage has emerged of the moment a London dog walker spotted what he thought was a crocodile swimming in the River Thames.

Chris Davies was walking his dog near Chelsea Harbour on Tuesday morning (October 10) he saw the "reptile" swimming among boats.

The passer-by immediately called the authorities to deal with the situation. But in the end, the dangerous animal revealed its real identity: it was a pond ornament floating in the Thames.

Harbour master Colin Bullock told the local Evening Standard: “It was just a pond ornament, that was it. It was quite obviously a plastic item and I just got a net.

“There was no reason to panic. We have had dolphins and porpoises before, but nothing like this.”

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Footage has emerged of the moment a London dog walker spotted what he thought was a crocodile swimming in the River Thames.