The mothership that dropped the doomed Titan sub ahead of its catastrophic dive to the Titanic wreckage has returned to shore. A Scottish student and four other men died when their sub imploded on a journey to the bottom of the ocean.

And pictures from Newfoundland today, as published by our sister title, The Mirror, show the main support ship, the Polar Prince, returning to St John’s Harbour in the Canadian province.

It is one of several ships that have returned to the harbour, after the Canadian Coast Guard (CCG) confirmed two other vessels were en route last night with a large crowd gathering at the port.

Suleman Dawood, a student at the University of Strathclyde, his father Shahzada, and British adventurer Hamish Harding were killed on board the Titan submersible.

Stockton Rush, the chief executive of the company responsible for the vessel, and French national Paul-Henri Nargeolet also died in the incident.

Titan submersible mothership MV Polar Prince return to St Johns Harbour, Newfoundland.
Titan submersible mothership MV Polar Prince return to St Johns Harbour, Newfoundland.

Yesterday, the Dawoods released a heartbreaking tribute to the father and son, saying they "passed onto the next leg of their spiritual journey hand-in-hand".

A statement read: “With profound sorrow, we mourn the tragic loss of Shahzada and his beloved son, Suleman, who had embarked on a journey to visit the remnants of the legendary Titanic in the depths of the Atlantic Ocean.

“In this unfathomable tragedy, we try to find solace in the enduring legacy of humility and humanity that they have left behind and find comfort in the belief that they passed on to the next leg of their spiritual journey hand-in-hand, father and son.

The pair were “each other’s greatest supporters and cherished a shared passion for adventure and exploration of all the world had to offer them.

“By being as they were with one another, they embodied valuable lessons on the pursuit of knowledge, exploration of the unknown, and bonds of familial friendship.

The ship has returned to the harbour.
The ship has returned to the harbour.

"Family values are a guiding beacon for the Dawood family, and Shahzada always strived to emulate these, teaching his children to do the same.”

The tribute came as the Transportation Safety Board of Canada (TSB) announced it would be conducting a safety investigation into the fatal implosion of the deep sea vessel.

In a statement issued before their ship arrived at the port, the CCG said: "The Canadian Coast Guard offers our sincere condolences to the family and friends of the crew of the Titan for their tragic loss. Search and rescue operations have concluded.

"The CCGS Terry Fox and CCGS Ann Harvey are en route to St John's. The CCGS John Cabot will remain on scene and will provide assistance and support to the recovery and salvage operations as requested by Maritime Rescue Coordination Centre Boston."

The TSB said a team of investigators had been deployed to St John's in Canada to "gather information, conduct interviews and assess the occurrence".

Suleman Dawood with his dad, businessman Shahzada.
Suleman Dawood with his dad, businessman Shahzada.

In a short statement confirming the investigation, the safety body said: "The TSB is launching an investigation into the fatal occurrence involving the Canadian-flagged vessel Polar Prince and the privately operated submersible Titan.

"In accordance with the Canadian Transportation Accident Investigation and Safety Board Act and international agreements, the TSB... will conduct a safety investigation regarding the circumstances of this operation conducted by the Canadian-flagged vessel Polar Prince.

"A team of TSB investigators is travelling to St John's, Newfoundland and Labrador to gather information, conduct interviews and assess the occurrence. In the coming days, we will co-ordinat our activities with other agencies involved."

The TSB will not determine civil or criminal liability and conducts investigations for "the advancement of transportation safety". The investigation comes after emails emerged from Mr Rush which dismissed safety concerns over the deep-sea vessel.

The exchanges with deep-sea exploration specialist Rob McCallum, reported by the BBC, show the company's chief executive say he was "tired of industry players who try to use a safety argument to stop innovation".

Hamish Harding
Hamish Harding has been described as a 'quintessential British explorer'

Mr McCallum could be seen telling Mr Rush that he was "mirroring that famous cry" of the Titanic's builders: "She is unsinkable." The broadcaster reported the email exchange ended when the company's lawyers threatened legal action.

The submersible lost contact with the tour operator an hour and 45 minutes into the two-hour descent to the wreckage, with the vessel reported missing eight hours after communication was lost.

In the days that followed the report that Titan had gone missing, the US Coast Guard said the vessel had a depleting oxygen supply that was expected to run out on Thursday.

A report from The Wall Street Journal said the US navy had detected a sound in the search area for the submersible on Sunday that was consistent with an implosion.

The Associated Press, citing a senior military official, reported that the navy passed on the information to the Coast Guard, which continued its search because the data was not considered by the navy to be definitive.

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