It’s mother natures version of a scythe-like bullwhip.

Dr. Simon Oliver, founder of the Thresher Shark Research and Conservation Project and a researcher based at University of Liverpool, filmed pelagic thresher sharks as they hunted off Pescador Island in the Philippines.

Their long, lethal tails take up half of their body, and this study confirmed what shark fishermen have known for years.

Back in 2010, another team managed to film the common thresher shark swiping at, and making contact with, tethered bait using their tails.

But Dr. Oliver told BBC News that these new observations provided the first clear evidence that “thresher sharks really do hunt with their tails.”

The findings are reported in the journal Plos One.

The vast schools of sardines in the water off Pescador Island in the Phillipines are feeding hot spots for these sharks, and the researchers encountered and filmed more than 60 occasions where the sharks bullwhipped their tails in an effort to kill the fish, BBC News reports.

In fact, the sharks overhead tail whip is so quick, that cameras had difficulties tracking the movement.

“It’s a cross between a bull whip and a medieval war machine – it’s extremely violent, extremely quick and it’s incredible to observe,” Dr. Oliver told BBC News.

To get past this technological boundary, the researchers broke down each attack into stages in order to record the animals’ exact movements.

They noted that the sharks accelerated, and then temporarily stalled themselves in the water by pulling their pectoral fins together. They then dipped their nose, and swiftly brought their tail upwards and over their heads.

The strikes do not always hit their intended target(s). But when they do, it is a lethal blow.

“The interesting thing about it was that these tail slaps were only successful about 60% of the time,” Dr. Oliver told BBC News. “But when they were successful they managed to kill more than one prey item.”