10-Foot Great White Shark Spotted Near Young Swimmers In Terrifying Video

Terrifying drone footage shows a massive great white shark cruising past some kids swimming off the Southern California coast ... and the children are blissfully unaware there's an apex predator below them.

Carlos Gauna -- known as The Malibu Artist online -- posted an anxiety-inducing video to Instagram Monday that shows a 10-foot shark approaching young swimmers in the water ... who apparently had no clue the shark was even there.

Carlos captioned the clip ... "I don't often get nervous but this was one of those rare instances where I did. The young swimmers had no idea."

Some folks think he should have alerted the kids -- even though that might have induced a panic and splashing that could attract more shark attention -- but he explained he was standing over a mile away when his drone spotted the shark.

Carlos said the great white appeared to have been injured by a boat propeller ... pointing out a gash across its back and dorsal fin.

He wrote ... "I watched it breach twice in one day (I assume that wound is itchy). And because of the injury I don't know if it's searching for easier prey or if it's more alert."

Carlos had apparently been monitoring this shark's behavior, saying it gets close to people "at a higher frequency."