Police say a Kansas visitor was charged after passengers restrained him aboard a returning tour boat.

KAILUA-KONA, Hawaii — A 62-year-old snorkel tour captain was stabbed aboard a fishing vessel off the Kona coast on April 16, then piloted the boat back to Honokōhau Harbor as police and medics waited, authorities said.

Hawaiʻi Island police said Avery Nissen, 21, of Overland Park, Kansas, was arrested and charged with second-degree attempted murder, first-degree assault and second-degree assault after the attack during a private three-hour snorkel tour. The case moved from an emergency response at sea to a criminal prosecution with $1.57 million bail, a not guilty plea and a trial date now set for Aug. 25.

The trip began as a private outing from Honokōhau Harbor, a busy North Kona launch point for ocean tours, fishing boats and charters. Captain Stan Lurbiecki, a longtime Hawaiʻi Nautical captain, had taken Nissen, Nissen’s mother and a sibling out on a 55-foot catamaran for a snorkel tour. The group went out Thursday afternoon, April 16. Lurbiecki later told local media that Nissen stayed aboard while the other two passengers entered the water. After the snorkel stop ended, the boat headed back toward the harbor. Lurbiecki said they were about 30 minutes from shore when Nissen got a fillet knife from the boat’s galley and attacked him without warning. “This is like the most random, wildest, craziest thing you’ll ever hear of,” Lurbiecki said after the attack.

Police said Kona patrol officers were called at 3:21 p.m. to Honokōhau Harbor, where the vessel was returning with the victim, the suspect, a crew member and passengers still on board. Officers reported that the captain had been attacked with a fillet knife during the tour. Police did not identify a motive. They said other passengers intervened and restrained Nissen after the stabbing. The captain suffered a stab wound to the lower abdomen and numerous knife cuts to his head and hands, police said. He was taken to Kona Community Hospital in stable condition. Lurbiecki later said he needed several blood transfusions and had lost a large amount of blood before reaching shore.

Lurbiecki’s account added a tense sequence after the knife struggle. He said he wrestled the knife away while Nissen continued to slash at him. Nissen’s mother tried to intervene, he said. Nissen then jumped from the boat into the ocean. Lurbiecki said he used a towel to hold pressure on one of his wounds and still turned the boat to recover Nissen from the water. Nissen climbed back aboard and sat with his mother for the rest of the trip, Lurbiecki said. Nissen’s sibling helped press on the captain’s wounds during the ride in. Lurbiecki said that help kept him from bleeding out before medics met the vessel at the harbor.

The case has focused attention on the rapid decisions made aboard the vessel after the attack. Police said the captain, the suspect and witnesses all returned to the same harbor, where officers could take Nissen into custody and medical workers could treat Lurbiecki. The tour boat was no longer only a commercial vessel carrying visitors back from the coast. It had become the scene of an alleged attempted murder, with witnesses, a weapon, injuries and competing statements to preserve. Police assigned the case to the Area II Criminal Investigation Section and listed Detective Bradley Llanes as the investigator. The department’s report number is 26-032768.

Prosecutors filed charges April 17 after police conferred with the Hawaiʻi County Office of the Prosecuting Attorney. Nissen was charged with attempted murder in the second degree, assault in the first degree and assault in the second degree. His bail was set at $1.57 million. Court coverage from Kansas City and Hawaii later reported that Nissen appeared in Kona District Court and that defense lawyers sought a mental health evaluation. Prosecutors did not object, and proceedings were suspended pending the evaluation. Online court records later showed Nissen pleaded not guilty at arraignment, his bail remained unchanged and a pretrial conference was set for July 13.

The attack also drew notice because of the setting. Snorkel tours off the Kona coast are a routine part of the island’s visitor economy, often carrying small groups to reefs and calm water along the leeward side of Hawaiʻi Island. This tour involved a private family group, a captain and a crew member, not a crowded excursion. The details released by police did not suggest a dispute before the stabbing, and Lurbiecki described the attack as unprovoked. Witness accounts cited in later court reporting said Nissen had appeared anxious and had been pacing and opening cabinets before the alleged attack. Authorities have not said what they believe caused the violence.

Lurbiecki’s years on the water became part of the public account after he described guiding boats for about 35 years. He said nothing like the attack had happened to him before. Hawaii Nautical’s leadership praised the crew’s conduct after the incident and said staff members acted with professionalism during a chaotic return to harbor. The captain’s injuries, the family members’ actions and the suspect’s return to the boat are all expected to remain key parts of the case as it moves forward. Police have asked people with information to contact investigators, while court filings and witness testimony may define what happened in the minutes before the knife was taken from the galley.

Avery Nissen remains charged as the case heads toward a July 13 pretrial conference and an Aug. 25 trial date. The motive remains listed as unknown, and the captain’s recovery continues after the attack at sea.

Author note: Last updated May 9, 2026.