THE passengers on board a submersible that went missing during a dive to the wreck of the Titanic are believed to have died. 

The Titan lost communication with tour operators on Sunday while about 435 miles south of St John’s, Newfoundland, during its voyage off the coast of Canada.

In a statement, the submersible's operating company OceanGate Expeditions have now said they believe the pilot and four passengers who were on board the vessel "have sadly been lost".

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We previously reported that 19-year-old Suleman Dawood, a student at Strathclyde University in Glasgow, was among them.

His father Shahzada was also on board, along with OceanGate CEO Stockton Rush, UK citizen Hamish Harding and French national Paul-Henri Nargeolet. 

The US Coast Guard offered its “deepest condolences” to their families after the tail cone of the submersible was found around 1600ft from the bow of the Titanic wreckage.

Glasgow Times: Suleman Dawood and his dad ShahzadaSuleman Dawood and his dad Shahzada (Image: Reuters)

In a press conference, Rear Admiral John Mauger said further debris was “consistent with a catastrophic loss of the pressure chamber”.

In a statement, OceanGate Expeditions said: "We now believe that our CEO Stockton Rush, Shahzada Dawood and his son Suleman Dawood, Hamish Harding, and Paul-Henri Nargeolet, 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.

"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 is an extremely sad time for our dedicated employees who are exhausted and grieving deeply over this loss.

"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.

"This is a very sad time for the entire explorer community, and for each of the family members of those lost at sea.

"We respectfully ask that the privacy of these families be respected during this most painful time."

At the press conference in Boston, Rear Admiral Mauger said: "This morning, an ROV, or remote operated vehicle from the vessel Horizon Arctic discovered the tail cone of the Titan submersible approximately 1600ft from the bow of the Titanic on the sea floor.

“The ROV subsequently found additional debris. In consultation with experts from within the unified command, the debris is consistent with the catastrophic loss of the pressure chamber.

"Upon this determination, we immediately notified the families.

"On behalf of the United States Coast Guard and the entire unified command, I offer my deepest condolences to the families. I can only imagine what this has been like for them.

"And I hope that this discovery provides some solace during this difficult time."