Thirty-four people are assumed dead after a boat fire Monday off the coast of Santa Cruz Island claimed the lives of diving enthusiasts who were apparently trapped below deck.

Authorities have called off a search for survivors. A Tuesday morning flight over the search area found no additional debris or signs of distress, authorities said.

“It is never an easy decision to suspend search efforts,” said U.S. Coast Guard Capt. Monica Rochester. “We know that this is a very difficult time for family and friends of the victims.”

The search was called off about 9:40 a.m. Tuesday, she said at a news briefing outside the Santa Barbara County Sheriff’s Office. Teams had conducted seven missions over nearly 24 hours by air, land and water. They searched an area of roughly 160 miles, she said.

Timeline:’Worst case scenario’: How the California boat fire unfolded

About 3:15 a.m. Monday, a mayday call reported the dive boat called Conception was engulfed in flames.

It was carrying 39 people in total — 33 passengers and six crew members. Five of the crew members escaped and were picked up by a Good Samaritan boat known as the Grape Escape.

Twenty victims’ bodies have been recovered, Santa Barbara County Sheriff Bill Brown said Tuesday.

Divers had spotted four to six other bodies in the wreckage, but had not yet been able to get to them, he said Tuesday.

“Today, efforts will be made to stabilize the boat so that divers can safely enter it, search it and recover additional victims,” Brown said Tuesday.

On Wednesday, authorities said they had recovered 33 of the 34 bodies.

LATEST:Last Conception boat fire victim's body recovered

As crews fought the fire early Monday, the boat sank about 20 yards off the island. It has since fully submerged.

Divers Tuesday planned to map the search area based on currents and the debris field, which is about a half-mile in size, Brown said.

This type of underwater search-and-recovery operation can be taxing and dangerous with divers operating in up to 65 feet of water.

The cause of the fire remains under investigation by federal, state and local authorities, including a National Transportation Safety Board team that arrived Tuesday, as well as the Coast Guard.

Brown said surviving crew members had written up their statements. Formal interviews were expected to happen Tuesday.

How the victims died

Brown was asked at the news conference whether it appeared the victims had been trapped in their sleeping area below below deck.

“That does appear to be exactly what happened,” he said.

Brown said there was a stairwell to get up and down the main entryway and an escape hatch. It would appear that both of those were blocked by fire, Brown said.

Brown said there was no indication that anyone who was below deck at the time of the fire had survived the tragedy, and that the one crew member who apparently didn’t survive appeared to have been sleeping below with passengers at the time of the fire.

The boat had three decks. A sleeping area was on the lower deck. A galley and a salon area were on a secondary deck. The third deck included the crews quarters and the bridge.

“It would be perfectly normal for the crew to be up on that third deck. That was their assigned location to sleep, and the bridge of the vessel was up there, as well,” Brown said Tuesday.

Brown clarified at the news conference that the first mayday call about the fire may have come from the Conception, rather than the Grape Escape. Subsequently, there were other mayday calls by the Good Samaritan vessel. He said the pair of audio clips have been confused by some as they were publicized.

About the boat and the excursion

The Conception was owned and operated by Truth Aquatics, a Santa Barbara-based company founded in 1974 and owned by Glen Fritzler.

The boat It had been chartered by Worldwide Diving Adventures, which says on its website that it has been taking divers on such expeditions since the 1970s.

According to Truth Aquatics’ schedule, the boat departed Santa Barbara at 4 a.m. Aug. 31 for a three-day dive trip and was expected to return at 5 p.m. Monday.

Truth Aquatics:Learn about company that owned the dive boat

It was anchored in a spot called Platt’s Harbor, a cove on the northwest end of Santa Cruz Island.

The island, part of the Channel Islands National Park off the Ventura County coast, has some of the most popular anchorages in the area.

The remote park, half of which is underwater, is known for having some of the best diving in the world.

Chartered dive boats come there from marinas throughout Southern California, said National Park Service spokeswoman Yvonne Menard.

What caused the fire aboard Conception?

Rochester and Brown both said there was no indication that the fire had been started by an explosion. Brown said there were possible reports from the Good Samaritan boat that explosions could be heard in the fire, but Brown said that would have occurred well after the fire started and there could have been any number of causes.

“There is no indication at this point of the investigation that there was an explosion that preceded the fire,” Brown said.

Brown said statements had been written by the surviving crew members and they would be entered into the investigation.

’No escape hatch’ for passengers? Read transcript of Santa Cruz boat mayday call

Rochester was asked at the news conference whether such boats are required to have smoke detectors and she replied that they are, in all breathing spaces.

The boat was required to be inspected annually and had to have a fixed and portable fire extinguishers at exit ways, as well as on the bridge and outside on deck, the Coast Guard reported.

According to the last inspection by the Coast Guard, all apparatus were on the boat.

The Coast Guard said it would work with the National Transportation Safety Board and other partner agencies to try to determine how the tragedy occurred and how to prevent future such incidents.

The NTSB held a news conference Tuesday afternoon in Santa Barbara about its investigation into the fire.

There is no requirement for a vessel of that size to have a black box on board, said Adam Tucker, the investigator-in-charge for the NTSB.

“We have not been informed that the vessel was fitted voluntarily with a black box,” he said.

An investigative team with the agency got to Santa Barbara at 10 a.m. Tuesday.

The agency is leading the safety investigation into the boat fire and expected to be on scene for seven to 10 days to collect what’s considered “perishable evidence,” said Jennifer Homendy, an agency board member.

“I’m 100% confident that our investigators will determine the cause of this fire, why it occurred, how it occurred and what is needed to prevent it from happening again,” she said.

A preliminary report is expected to be released within roughly 10 days. A final report likely will take 12 to 24 months.

“In between that time, we have many times issued urgent safety recommendations when we feel that there is a safety concern that needs to be addressed,” Homendy said.

The NTSB also asked for the public’s help. Anyone with photos, video or other information that could help with the investigation was asked to email the team at witness@ntsb.gov.

This is not the first fire they have investigated on a small passenger vessel. In 2018, they led an investigation of small vessel fire in Port Richey, Florida.

About the Santa Cruz Island boat fire victims

The 20 victims’ bodies recovered by Tuesday morning included 11 females and nine males.

Many, if not all, the bodies will have to be identified using DNA samples from family members, according to the Santa Barbara County Sheriff’s Office.

A call center has received more than 100 calls from family or friends who believe that loved ones were on board the Conception, Brown said.

So far, family members of 30 of the victims have connected with the Sheriff’s Office. Investigators have not yet connected with family members of the other four victims.

Those who died:Who were the victims? We're starting to find out

Authorities were beginning to map DNA profiles of the victims Tuesday, so those could be compared with samples from parents or siblings, Brown said.

A special team from the California Department of Justice was assisting in the identification process with a rapid DNA analysis tool that also was used after last year’s deadly Camp Fire in Butte County.

Brown said DNA identification was necessary due to “thermal damage” from the fire.

No autopsies have yet been conducted to determine the causes of death, according to Brown.

One man from the Conception was taken to St. John’s Regional Medical Center early Monday, according to a spokeswoman for the Oxnard hospital. He was in good condition and is still in the hospital, she said.

Family assistance center

Authorities have a set up a family assistance center for family members to receive more information, but it was mostly quiet Tuesday morning.

A few children and adults walked inside the center around 9 a.m. and declined to speak with reporters.

The center is meant to be a place where family members and friends of those affected by the fire can get information, resources, support and counseling, according to Suzanne Grimmesey, of the Santa Barbara County Department of Behavioral Wellness.

The center has chaplains and other clergy members, hospice representatives, sheriff’s and fire representatives and others who may provide assistance and resources.

Officials say it will be open from 9 a.m. to 6:30 p.m. daily though Thursday, but days and hours could be extended as necessary.

Grimmesey said if the public knows someone affected by the incident, talk to them, make sure they know about the resources at the showgrounds.

Concerned family members are being asked to call 833-688-5551.

Conception dive boat fire coverage

Wondering more about the company that owns the boat? Or what time Monday morning the incident started? Check out our what we know story for more answers about the Santa Cruz Island boat fire incident.

CHECK BACK: This is a developing article, we will update as more information comes available.

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