These horrifying images show the moment a monstrous turtle with bear-like claws surfaces beneath a kayak.
Shala Holm, 67, was fishing with her daughter, Avery, on the Mississippi River near Brainerd, in the US state of Minnesota, when they got a surprise.
The mum described the moment they saw the giant reptile.
She recalled: "Suddenly my daughter said, 'mom, be quiet, I hear something breathing.'
"It took a while before we saw the nose of a turtle swimming toward the kayak. As it got closer, we saw how big it was.
"He dove under the kayak and latched himself onto the fishing basket with his nails. We were so freaked out about the size."
What they encountered was a snapping turtle, a prehistoric-looking reptile feared for its powerful bite.
Shala estimated it was 29 inches across, which is bigger than the tyre of a commercial airliner.
Shala continued: "People asked if I was afraid, and I must admit at the time I was, which is kind of silly because I am bigger than he was and hopefully smarter.
"I guess because we were so close to him, being in the kayak, and I didn't know how badly he wanted those fish and if he would try and get into the kayak.
"I wasn't sure how I would get him off the basket. I was nervous about grabbing the handle of the basket, I wasn't sure how badly he wanted the fish and how aggressive he might be.
"We've all heard stories of snappers snapping a broomstick handle in two."
Once they'd shaken the basket free, the pair got away as quickly as they could.
When they returned the next day to get a picture of the monster - it was still there.
Shala said: "We never heard him or saw him again until he was clinging onto the basket.
"My heart was racing but I was able to grab my phone and snap a few pictures.
"I was amazed at the size of his outstretched legs; his feet were the size of my fist and then add those nails!
"I was afraid he might claw his way on top of the basket."
Snapping turtles are native to the US and southern Canada and can live to be more than 100 years old.
Shala later sent her snaps to the Minnesota Department of Natural Resources, who estimated that the one she encountered might have been 15 years old.
She hopes to see the creature again when she returns to Niemeyer's Rugged River Resort next year.
As well as its powerful bite, the snapping turtle is also known for its highly-manoeuvrable neck, meaning that even a handler who picks it up by the sides of its shell risks being bitten.
Their claws are said to be as sharp as a bear's, though they use them for digging and gripping rather than attacking.
