A Pennsylvania man was attacked by a rare shark off Hawaiian waters on Saturday.

Eric Schall and his friend Steve Gruenwald flew to Hawaii to swim the Kaiwi Channel. 

The swim is 26-miles from Molokai to Oahu and it’s only been completed by 63 people. 

Bill Goding is one of them and now helps others who attempt and succeed the journey, he tells KHON2 what happened overnight. 

He says both men are trained swimmers and have been planning on swimming the Kaiwi Channel for a while. 

In fact, Gruenwald attempted the journey last year but fell ill. The two men decided to do it together this year. 

But strong winds over the week delayed their original plans. 

“The window looked very good for Friday and Saturday,” Goding said. “The winds died down and they began their swim on the west side of Molokai at 6:26 p.m. [Friday].”

Goding says about half way through the swim Gruenwald became ill again and went back on the boat. 

“Eric continued and of course it was night, and he was struck by a Cookiecutter shark,” Goding said.

Both Emergency Medical Services and Goding say Schall was bit in the abdomen. 

EMS said Schall was about nine hours into the swim.

Goding said the escort boat grabbed Schall immediately and began first aid. He was then brought to Hawaii Kai boat ramp and taken to Queen’s Hospital in serious but stable condition. 

The first human attack by a Cookiecutter shark happened to Maui resident and swimmer Mike Spalding. He was swimming the Alenuihaha Channel at the time.

Experts say Cookiecutter sharks average a foot and a half in length and spend most of their time in deep water—but come to the surface at night to feed. 

“This is not a shark you would normally see, it’s a very small shark but very nasty,” Goding said.

Even though it’s small, the shark has been known to attack dolphins, whales and seals. 

“Many people have done this swim and it’s just very unfortunate that this happened,” Goding said.

Scientists have said that swimmers should use caution when out in deep waters at night because Cookiecutter sharks are attracted to light.