A 23-year-old man was set to undergo surgery Sunday, a day after he was attacked by a shark in the waters off Pounders Beach near Laie.

The stand-up paddleboarder was rescued by a group of alert surfers who fashioned a couple of tourniquets on the man’s right arm before guiding him to shore.

The man was transported in serious condition to a hospital emergency room by Honolulu Emergency Manage­ment Services Department personnel.

Ryan Hailstones was one of the surfers who came to the man’s aid at about 8:15 a.m. a quarter mile or so offshore.

“It was a nice beautiful morning, and there was a lull in the waves,” Hailstones said. “All of a sudden, I heard someone screaming, ‘Help, shark, help, help!’ I looked over and saw a shark fin going into him, and it was going back and forth, back and forth.”

That’s when a wave crashed into the man, he said, and the shark let go. The man was bleeding badly from a bite on the right arm above the elbow, Hailstones said.

“It was every surfer’s nightmare,” he said.

A group that included a North Shore lifeguard and a professional surfer converged on the man quickly and worked to tie surfboard leashes on his arm to help stop the bleeding, he said. Because of the surf site being so far from shore, it took about 15 minutes to paddle him in.

Without those tourniquets, the man probably would have bled out before he reached the shore, said Hailstones, who is also a certified lifeguard. The group cut through an oceanfront property to get to the street, and the ambulance arrived in about five minutes.

Hailstones said he later contacted the victim, who said he was going into surgery.