US Coast Guard says human remains have been discovered in the wreckage of Titan submersible.

The sub, which imploded on a deep dive to the Titanic, was unloaded in St John’s, Canada, on Wednesday.

Among the debris were the landing frame and rear cover of the sub.

A formal analysis of presumed remains will be conducted by US medical professionals, the coast guard announced.

Currently, the agency is investigating the causes of the disaster. It will be transported to a US port for analysis and testing by the Coast Guard’s Marine Board of Investigation (MBI).

MBI Chair Captain Jason Neubauer said in a statement that 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”.

“I am grateful for the coordinated international and interagency support to recover and preserve this vital evidence at extreme offshore distances and depths,” Cpt Neubauer said.

Investigation continues

Approximately 90 minutes into diving to view the famous 1912 shipwreck in the north Atlantic, the vessel imploded, killing all five aboard.

Among the passengers were Stockton Rush, 61, the head of OceanGate, which organized the dive; Hamish Harding, 58; Shahzada Dawood, 48, and his son Suleman Dawood, 19; and Paul-Henry Nargeolet, 77.

Initially, officials were skeptical about recovering any bodies.

“This is an incredibly unforgiving environment down there on the seafloor,” Coast Guard Adm John Mauger said, shortly after the loss of the vessel was confirmed.

According to Cpt Neubauer, investigators would take “all precautions” if human remains were found and the investigation would likely include a formal hearing.

The coast guard says five major pieces of the sub have been found in a large debris field near Titanic’s bow.