(MIAMI) -- A vacationing dive-boat passenger died after a rogue wave capsized a catamaran Thursday, tossing 21 passengers and two crew members into the ocean off the coast of Pompano Beach, Fla.
The 45-foot boat capsized Thanksgiving Day afternoon as it approached Hillsboro Inlet when, witnesses say, a large wave came out of nowhere and flipped the boat over. Passengers managed to climb out of the water and onto the overturned hull until help arrived.
But Nina Poppelsdorf, 54, died after being pinned underneath the capsized catamaran, investigators said.
Three other passengers were taken to a hospital with non-life threatening injuries and later released, ABC News affiliate WPLG-TV reported.
Pompano Beach Fire Rescue was notified around 1 p.m. about the incident when the Coral Princess was hit by a rough wave after a Thanksgiving Day dive trip. First responders arrived on the scene in minutes where they found the catamaran "in pieces, upside down in the water," agency spokeswoman Sandra King said.
As beach goers called 911, nearby boaters raced toward the accident, pulling people onto wave runners and rescue boats.
"Chaos. Just people in the water. Just unbelievable," one eyewitness said.
Surviving passengers began gathering on the beach to make sure everyone was accounted for.
"We kept hearing back and forth, just trying to get a head count on everybody, and they were missing one," eyewitness Greg Oars said.
King of fire rescue said, "During the rescue, it got pretty dicey and scary because we were told there were more people. There may be people missing."
Divers pulled Poppelsdorf out of the water and began to perform CPR. Poppelsdorf, who was visiting South Florida from New Mexico with her nephew, was pronounced dead at the hospital, according to WPLG. The Broward County Medical Examiner will determine the cause of her death.
Investigators worked through the night to question the survivors about what happened in the moments before the wave hit the catamaran.
"[The] wave caught it from behind and it flipped as [the captain] was coming in the harbor," an unidentified passenger told ABC News. "He was trying to time it. He didn't time it right and then it just flipped."
Investigators are still trying to determine the cause of the accident but they say the catamaran did not appear to be over capacity.
"Right now, it looks like this is a tragic accident," Broward Sheriff's Office spokeswoman Dani Moschella said. "What started out as a gorgeous day on the water for 23 people ended in tragedy."
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