The possible remains and shattered remnants of the Titan, destroyed while diving to the wreck of the Titanic, and what were believed to be human remains were carried to port in St John's in Newfoundland, Canada, by the Canadian-flagged vessel Horizon Arctic.
The port is about 650 kilometres north of the site of last week's accident.
The evidence will be transported to a US port for analysis and testing by a marine board of investigation convened this week to conduct a formal inquiry into the loss of the Titan, the US coast guard said on Wednesday.
"There is still a substantial amount of work to be done to understand the factors that led to the catastrophic loss of the Titan and help ensure a similar tragedy does not occur again," Coast Guard Chief Captain Jason Neubauer said in a statement released late Wednesday afternoon.
US medical professionals also "will conduct a formal analysis of presumed human remains that have been carefully recovered within the wreckage at the site of the incident", Capt Neubauer added.
The marine board will share the evidence at a future public hearing whose date has not been determined.
Video from the Canadian Broadcast Corp showed what appeared to be the nose of the submersible and other shattered fragments wrapped in white tarp pulled up by a crane from the deck of the Horizon Arctic on Wednesday morning.
Footage also showed a shattered piece of the Titan's hull and machinery with dangling wires being taken off the ship at St John's, where the expedition to the Titanic had begun.
Examination of the debris is expected to shed more light on the cause of the catastrophic implosion that shattered the Titan on June 18 as the 6.7-metre vessel carried five people on a voyage to the century-old shipwreck of the Titanic in the North Atlantic.
Canada's Transportation Safety Board, conducting its own inquiry, said its investigators had completed preliminary interviews with the crew of Titan's Canadian-flagged surface support vessel, Polar Prince, and seized that ship's voyage data recorder.
The board also said it had "inspected, documented and catalogued" all the materials recovered from the accident site before they were turned over to US authorities.
Fragments of the submersible, which had lost contact with its support surface ship about one hour and 45 minutes into a two-hour dive, were found littering the seabed about 490m from the bow of the Titanic wreck four days later.
The discovery by a robotic deep-sea diving vehicle scrounging the ocean floor more than 3km down ended a multinational search that captured worldwide media attention and sealed the fate of the five people aboard.
Among the dead was Stockton Rush, the submersible pilot and chief executive of US-based OceanGate Expeditions, which owned and operated the Titan.Â
Also killed were the British billionaire Hamish Harding, 58; Pakistani-born businessman Shahzada Dawood, 48, and his 19-year-old son, Suleman; and 77-year-old French oceanographer Paul-Henri Nargeolet.
The accident has raised questions about the unregulated nature of such expeditions and the decision by OceanGate to forego third-party industry review and certification of Titan's novel design.
"Our team has successfully completed off-shore operations, but is still on mission and will be in the process of demobilization from the Horizon Arctic this morning," Pelagic Research, which operates a robotic vehicle used in recovering the debris, said in a statement.
With AP
