Hammerhead Shark Spooks Swimmers at Florida Beach

— -- A hammerhead shark shocked beachgoers in Florida when it swam right up to the shore, prompting terrified swimmers to frantically flee from the water.

And the man who caught it all on video, Dan Flynn, said the hectic scene was "extraordinary."

"I've seen sharks before but I've never seen a shark get that close," he told ABC News today. "It was almost interacting with humans. From our vantage point, we could see the shark going towards a lady swimmer. And her back was to the shark, and she was unaware. You can hear people screaming in the video. I yelled, 'Get out of the water!'"

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Flynn, who lives in New Orleans, watched the scene unfold Tuesday from the fishing pier in Navarre, Fla., while on vacation with his family.

From above, he could see directly into the clear water. The shark was probably 10-feet-long, he said.

"Someone just yelled shark and I started taping," he said.

Flynn estimates that the shark got within 10 feet of the shore. It swam around for about 10 or 15 minutes, he said, before retreating back into the sea.

Swimmers were spooked but wasted no time getting back into the water, he said. His videos of the shark quickly went viral after he posted them on Facebook.