Mysterious fin spotted lurking in River Thames in London

A mysterious finned creature was spotted swimming down the River Thames in west London.

Charlotte Webb was walking near Hammersmith Bridge on Monday (22 July) when she witnessed the unusual sight in the water.

She first thought it was a bean bag, but it later appeared to be a fin.

"It looked around 5ft which makes it a tope shark according to the comments," Webb said.

The Thames estuary is known to be home to at least five different species of shark, including the critically endangered tope shark, according to ZSL London Zoo.