LOS ANGELES (CBSLA/AP) — While it was still unclear what caused the tragic dive boat fire off Santa Cruz Island that killed 34 people last year, newly released federal documents reveal possible problems in the training of crew members.

Hundreds of pages have been released in the federal investigation into the Sept. 2, 2019 blaze aboard the 75-foot charter boat Conception — anchored about 20 yards off Santa Cruz Island and 22 miles southwest of Santa Barbara.

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Five crew members and the captain of the boat survived. They were all interviewed as part of the investigation.

Cullen Molitor, the boat’s second captain, told investigators that he saw sparks flash when he plugged in his cellphone hours before the deadly Labor Day weekend fire. In total 33 passengers and one crew member died while sleeping below deck.

Ryan Sims, who had been working aboard the boat for just three weeks, told investigators he had asked the captain, Jerry Boylan, to discuss emergency plans the day before the fire. Boylan reportedly told him: “When we have time.”

“I didn’t know what the procedures were supposed to be,” Sims said. Other crew members also said they weren’t familiar with safety procedures.

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Molitor also told investigators that a power strip was filled with flashlights, cameras and strobes as they charged overnight on a table in the galley. That crew member said the items had been used during a night dive and were wet.

He said the boat was equipped with two smoke detectors in the bunk room and two in the galley, but said he did not hear any alarms after a crew member woke him. He wasn’t sure if they were wired together to sound at once, but said he would expect to hear them from where he was sleeping.

“One thing we never heard was any screams or banging or anything from the boat, both while we were on it or when we were close,” Molitor said.

The captain of the boat is facing criminal charges related to the tragedy.

The National Transportation Safety Board’s report on the cause of the fire is set to be released at a public hearing in Washington next month.

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