Missing Titanic submersible live updates: Texts show OceanGate CEO dismissed concerns

The Explorers Club reacted to news of the submersible's implosion, saying in a letter to members on Thursday: "Our hearts are broken."

President Richard Garriott de Cayeux noted that two of the passengers lost in the implosion -- Hamish Harding and Paul-Henri Nargeolet -- were members of the Explorers Club, while OceanGate CEO Stockton Rush was a friend of the society who had conducted lectures at its headquarters.

"Hamish Harding is a dear friend to me personally and to The Explorers Club," Garriott de Cayeux said. "He holds several world records and has continued to push dragons off maps both in person and through supporting expeditions and worthy causes."

Nargeolet was "one of the foremost experts on submersible expeditions to the Titanic," Garriott de Cayeux said.

"They were both drawn to explore, like so many of us, and did so in the name of meaningful science for the betterment of mankind," he continued. "They pushed themselves in their entrepreneurial pursuits as they did in exploration."

In reacting to news of the OceanGate submersible implosion, "Titanic" director James Cameron told ABC News that he was "struck by the similarity of the Titanic disaster itself, where the captain was repeatedly warned about ice ahead of his ship and yet he steamed at full speed into an ice field."

Cameron, who has built his own submersible, was critical of OceanGate's use of a carbon-fiber hull, calling it "fundamentally flawed."

OceanGate CEO Stockton Rush, who was among the five passengers killed on the submersible, had previously said he believed a sub made with carbon fiber would have a better strength-to-buoyancy ratio than titanium.

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James Cameron on similarities between Titanic wreck and tourist sub

The director of “Titanic” said “many people in the community were very concerned” about the Titan submersible.

ABCNews.com

"Titanic" director James Cameron, who has explored the wreckage site himself, called the implosion "quite surreal" and noted that one of the passengers killed, Paul-Henri Nargeolet, was a friend of his.

"For him to have died tragically in this way is almost impossible for me to process," Cameron told ABC News Thursday.

Coast Guard officials said a remote-operated vehicle found the tail cone of the Titan submersible about 1,600 feet from the bow of the Titanic Thursday morning.

Additional debris found was "consistent with the catastrophic loss of the pressure chamber," Rear Adm. John Mauger, the First Coast Guard District commander, said during a press briefing.

The passengers' families were immediately notified.

Five major pieces of debris were found, including the nose cone, officials said.

The debris indicates there was a "catastrophic implosion" of the vessel, Mauger said.

It's too early to tell when the implosion occurred, officials said.

"This is an incredibly unforgiving environment down there on the seafloor," Mauger said.