A man and his friend have made an "incredible" discovery while scuba diving in a river.
Derek Demeter and Henry Sadler were diving in the Peace River in the US state of Florida on April 25 when they uncovered a giant Columbian mammoth leg bone.
"In Florida between two million to 10,000 years ago, Florida had these giants roam the prehistoric savannah grasslands," Mr Demeter wrote on Facebook.
The bone measured about 1.2-metres-long and weighed around 22kg.
Mr Demeter, an amateur palaeontologist, told Fox 35 while they can't pinpoint exactly how old the bone is, he believes it wandered the Earth between 2.6 million and 10,000 years ago.
"This one's much more dense, so we kind of think it's somewhere in the middle. Probably 100,000 years old," Mr Demeter suspected.
"The thing I love about it is, just like astronomy, it's time travelling. It plays with the imagination so you go 'Wow, what was going on at this time?'"
According to Fox 35, the diving buddies have also uncovered parts of an extinct shark and a tooth belonging to a saber-tooth tiger.
Colombian Mammoth leg bone an 'incredible find'
Mr Sadler posted pictures of him holding the mammoth bone on Instagram, saying he was fortunate to uncover the tooth and bone.
"Pictured here is a Colombian Mammoth leg bone, and while not as rare as the [tooth], it is still an incredible find," he wrote.
"It is almost completely undamaged and very well mineralised. Huge shoutout to [Derek Demeter] for helping me unearth this beast."
People in awe of the discovery agreed on Facebook it was "awesome".
"That's incredible," one said.
"That's a treasure," another commented.
"Amazing. Just amazing," a third added.
Mr Demeter added the bone was now sitting in his Mr Sadler's classroom so children could look at it and learn more about the Ice Age.
Do you have a story tip? Email: email@example.com.