A mother and daughter had a fright when they threw a stone at a log that turned out to be an alligator!
Stacey Clayton was having a stroll with her daughter around St Andrew's Pond in St Blazey, Cornwall, on Saturday morning when they spotted the object.
But when it moved, they decided it was a caiman, a 60cm alligator which comes from South America, and ran home.
The RSPCA are now hunting for the beast, which they think may have been abandoned after it grew too big.
One theory is that, if it is an alligator, the caiman may now be hiding in marshland nearby and could return to the pond.
Rob Skinner, from the RSPCA, said: "Caiman have sharp teeth and could give a nasty bite so if people do see this creature they should leave it alone and notify us immediately."
However the animal charity said it was also possible the creature had already died from the cold.