It could take months for the Coast Guard to complete an investigation into what caused a 65-foot mast on a Waikiki commercial catamaran to snap and kill a 13-year-old boy and seriously injure two other people on Friday.

Chief Petty Officer Marsha Delaney, spokeswoman for the Coast Guard, said officials are conducting extensive interviews with Na Hoku II crew members and witnesses aboard the boat at the time of the accident. They are also investigating the ship's equipment, including the mast.

"It is a very detailed, thorough process. That's why it takes quite a while," she said.

Meanwhile, the Honolulu Medical Examiner's Office released autopsy findings for 13-year-old Jordan James Loser, of Riverside, Calif., who died as a result of the incident. Loser suffered blunt-force injuries to the head and neck. The medical examiner classified the death as an accident.

Attorney Mike Formby, whose firm is representing Na Hoku II owner John Savio, said Savio is cooperating with the joint investigation of the Coast Guard and the state Department of Land and Natural Resources.

"I can tell you that at the time of the accident, the Na Hoku was operating under a valid certificate of inspection from the Coast Guard," said Formby.

The vessel remains docked at the Ala Wai Boat Harbor fuel pier, where its equipment is being preserved for investigation, Formby said.

A 41-year-old woman who suffered serious injuries was released from The Queen's Medical Center Saturday after being kept overnight for observation. A second woman, 40, was treated at Straub Clinic & Hospital on Friday and released.

The boy's parents, David and Catherine Loser, were part of a group of employees of the AAA who were being rewarded for their work with a vacation to Hawai'i last week. The family went home to Riverside on Sunday.

The accident occurred near the Diamond Head buoy around 4:20 p.m. Friday. According to witnesses aboard the 45-foot sailboat, Jordan was pinned face down on the upper deck after the aluminum mast suddenly snapped and struck him. Passengers and crew were unable to free the boy, and firefighters responding to the emergency were only able to remove the mast by using air bags.

David Loser, the boy's father, told the Press-Enterprise of Riverside, Calif., that winds were blustery and Jordan had been enjoying the cruise in the bow netting stretched between the double hulls. When the boat turned and the ride got rougher, the boy moved aft, closer to his parents, and held onto the mast. Jordan was there when the mast snapped and pinned him.

Jordan, who was unresponsive as rescuers worked to free him, was airlifted to Queen's, where he was pronounced dead.

Savio said Friday night that he had no idea what could have caused the mast to buckle.

Reach Loren Moreno at lmoreno@honoluluadvertiser.com.