Four days after going missing, the company operating the Titanic research submersible addressed the fate of its passengers.

OceanGate said in a June 22 statement that they "now believe" that all five people on board—company CEO Stockton Rush as well as passengers Hamish Harding, Paul-Henri Nargeolet, Shahzada Dawood and his 19-year-old son Suleman Dawood—"have sadly been lost."

"These men were true explorers who shared a distinct spirit of adventure, and a deep passion for exploring and protecting the world's oceans," the statement continued. "Our hearts are with these five souls and every member of their families during this tragic time. We grieve the loss of life and joy they brought to everyone they knew."

OceanGate reflected on the challenging time for all involved in the mission and rescue efforts.

"This is an extremely sad time for our dedicated employees who are exhausted and grieving deeply over this loss," the company said. "The entire OceanGate family is deeply grateful for the countless men and women from multiple organizations of the international community who expedited wide-ranging resources and have worked so very hard on this mission. We appreciate their commitment to finding these five explorers, and their days and nights of tireless work in support of our crew and their families."

The company concluded its statement by asking for privacy for the families impacted by the tragedy.

The Coast Guard announced on Twitter June 22 that a remotely operated vehicle (ROV) discovered debris within the search area near the Titanic.

In a press conference later in the day, officials confirmed that the debris was from an external part of the submersible, which they said was found about a third of a mile away from the 1912 ship wreckage.

"This morning an R.O.V. from the vessel Horizon Arctic discovered the tailbone of the Titan submersible," First Coast Guard District commander Rear Adm. John Mauger said, "approximately 1,600 feet from the bow of the Titanic on the sea floor."

The vehicle discovered five major pieces of debris, which he said is "consistent with the catastrophic loss of the pressure chamber." The admiral added, "Upon this determination we immediately notified the families." 

A senior U.S. Navy official told NBC News June 22 that an analysis found an acoustic anomaly that was "consistent with an implosion or explosion in the general vicinity" of where the Titan was diving, though the information was not definitive.  

Officials said at the press conference that it's too early to determine the timing of any potential incident. They've had sonar buoys in the water for the past 72 hours nearly continuously, but did not detect any catastrophic events in that time period.

Authorities said they will continue to investigate the field of debris as they hope the families start to gain some closure. 

The submersible Titan—a 21-foot vessel—as well as its five-person crew, disappeared in the Atlantic Ocean on June 18 just over an hour into their OceanGate Expeditions tour while en route to the RMS Titanic wreckage.

Following Titan's disappearance, a massive search-and-rescue mission was launched to find the passengers onboard.

Prior to the discovery of the debris, Coast Guard officials estimated that Titan's 96-hour oxygen supply was expected to run out in the morning of June 22.

To learn more about all of the passengers onboard the Titan, keep reading...

On June 18, 2023, a deep-sea submersible Titan, operated by the U.S.-based company OceanGate Expeditions and carrying five people on a voyage to the wreck of the Titanic, was declared missing. Following a five-day search, the U.S. Coast Guard announced at a June 22 press conference that the vessel suffered a "catastrophic implosion" that killed all five passengers on board.

Pakistani-born businessman Shahzada Dawood and his 19-year-old son Suleman Dawood, both British citizens, were also among the victims.

Their family is one of the wealthiest in Pakistan, with Shahzada Dawood serving as the vice chairman of Engro Corporation, per The New York Times. His son was studying at the University of Strathclyde in Glasgow, Scotland.

Shahzada's sister Azmeh Dawood told NBC News that Suleman had expressed reluctance about going on the voyage, informing a relative that he "wasn't very up for it" and felt "terrified" about the trip to explore the wreckage of the Titanic, but ultimately went to please his father, a Titanic fan, for Father's Day.

The Dawood Foundation mourned their deaths in a statement to the website, saying, "It is with profound grief that we announce the passing of Shahzada and Suleman Dawood. Our beloved sons were aboard OceanGagte's Titan submersible that perished underwater. Please continue to keep the departed souls and our family in your prayers during this difficult period of mourning."

OceanGate CEO Stockton Rush was the pilot of the Titan. The entrepreneur—who founded the research company in 2009 in Everett, Wash.—had long been interested in exploration. Rush, 61, previously said he dreamed of becoming the first person on Mars and once said that he'd "like to be remembered as an innovator."

In addition to leading voyages to see the remnants of the Titanic, Rush had another surprising connection to the historic 1912 event: His wife Wendy Rush is the great-great-granddaughter of a couple who died on the Titanic, Ida and Isidor Straus.

British billionaire Hamish Harding confirmed he was a part of the mission in a June 17 Instagram post, a day before the submersible went into the water and disappeared.

"I am proud to finally announce that I joined @oceangateexped for their RMS TITANIC Mission as a mission specialist on the sub going down to the Titanic," he wrote. "Due to the worst winter in Newfoundland in 40 years, this mission is likely to be the first and only manned mission to the Titanic in 2023. A weather window has just opened up and we are going to attempt a dive tomorrow."

Harding—the chairman of aircraft company Action Aviation—said the group had started steaming from St. Johns, Newfoundland, Canada and was planning to start dive operations around 4 a.m. on June 18. The 58-year-old added, "Until then we have a lot of preparations and briefings to do."

His past explorations included traveling to the deepest part of the ocean in the Mariana Trench, telling Gulf News in 2021, "It was an incredibly hostile environment. To travel to parts of the Challenger Deep where no human had ever been before was truly remarkable."

The Dubai-based businessman also circumnavigated the Earth by plane with the One More Orbit project and, last year, took a trip to space on Amazon founder Jeff Bezos' Blue Origin New Shepard rocket. Harding shared his love for adventure with his son Giles, described as a "teen explorer" on his Instagram.

As for the fifth member, a representative for French explorer Paul-Henri Nargeolet told the New York Times that he was a passenger on the Titan, with Harding also referencing him on Instagram as a member of the team. 

The Times described him as a maritime expert who was previously part of the French Navy. The 71-year-old was a bonafide Titanic specialist and has traveled to the wreckage 35 times before. Nargeolet served as the director of RMS Titanic, Inc., a company that researches, salvages and displays artifacts from the famed ship, per the outlet. 

Alongside fellow passenger Hamish Harding, he was a member of The Explorers Club, founded in 1904.

As Harding noted in his post, the submersible—named Titan—was a part of an OceanGate Expeditions tour that explores the wreckage of the RMS Titanic, which infamously sank in 1912.

The company expressed its sympathies to the families of the victims. "These men were true explorers who shared a distinct spirit of adventure, and a deep passion for exploring and protecting the world's oceans," OceanGate said in a statement. "Our hearts are with these five souls and every member of their families during this tragic time. We grieve the loss of life and joy they brought to everyone they knew."

This story was last updated on June 22, 2023 at 3:30 p.m. PT with additional details.

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