It was not immediately clear where the debris was headed.

Canadian and US authorities have in the past week announced investigations into the incident,which has raised questions about the unregulated nature of such expeditions.

The deep-sea submersible operated by OceanGate Expeditions was discovered in pieces on the seabed some 1600 feet (488 metres) from the bow of the Titanic by a robotic diving vehicle last week,ending a multinational five-day search for survivors.

“Our team has successfully completed off-shore operations,but is still on mission and will be in the process of demobilisation from the Horizon Arctic this morning,” Pelagic Research,which operates the robotic vehicle,said in a statement. It declined to comment further,citing confidentiality reasons.

Footage also showed a shattered part of the hull and machinery with dangling wires being taken off the ship at St John’s,where the expedition to the Titanic had set off from.

One of the experts the Coast Guard consulted with during the search said analysing the physical material of recovered debris could reveal important clues about what happened to the Titan. And there could be electronic data,said Carl Hartsfield of the Woods Hole Oceanographic Institution.

“Certainly all the instruments on any deep sea vehicle,they record data. They pass up data. So the question is,is there any data available? And I really don’t know the answer to that question,” he said Monday.

Representatives for Horizon Arctic did not respond to requests for comment.

Coast Guard representatives declined to comment on the investigation or the return of debris to shore on Wednesday.

No bodies have been recovered,though Coast Guard officials said days earlier that they were taking precautions in case they encountered human remains during the investigation.

Reuters,APwith staff reporter

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