WATCH: Swimmers have close encounter with hammerheads

A group of swimmers had an incredible encounter with a school of hammerhead sharks in Hawaii.

Once the swimmers take the plunge, underwater video shows more than a dozen hammerhead sharks swimming together around the Kona area of Hawaii.

Jeff Leicher, the videographer who shot the footage, says winter is prime time for marine life like sharks and whales, there. He's not surprised that this pack of scalloped hammerhead sharks swam up and stuck around.

Adult hammerheads can grow up to 14 feet and sometimes swim in packs of 100.

The hammerhead is not typically aggressive toward humans and is considered to be safe around divers.