The US Coast Guard has reported the recovery of more debris and suspected human remains from a privately owned submersible that experienced a catastrophic failure in June during a mission to explore the Titanic. All five individuals on board the submersible, named Titan and operated by the US-based company OceanGate, tragically lost their lives when the vessel imploded during its descent on June 18.

The confirmation of the sub’s failure came on June 22, marking the end of a days-long rescue mission that captured global attention. In response, the Coast Guard has initiated its highest level of investigation, known as a Marine Board of Investigation, to probe the circumstances surrounding the accident.

On October 4, the US Coast Guard revealed in a statement that marine safety engineers with the Marine Board of Investigation had recovered and transferred remaining Titan submersible debris and evidence from the North Atlantic Ocean seafloor. Additionally, presumed human remains were carefully collected from within the Titan’s debris and transported for analysis by US medical professionals.

Some wreckage and presumed human remains had also been recovered in late June as part of the initial response to the disaster. The Coast Guard has been working in coordination with the US National Transportation Safety Board (NTSB) and other international investigative agencies to schedule a joint evidence review of the Titan debris.

The five individuals on board the Titan at the time of the accident included British explorer Hamish Harding, French submarine expert Paul-Henri Nargeolet, Pakistani-British tycoon Shahzada Dawood and his son Suleman, and Stockton Rush, CEO of OceanGate Expeditions, the operator of the sub.

The debris field was discovered at a distance of 1,600 feet (500 meters) from the bow of the Titanic, which rests approximately 400 miles off the coast of Newfoundland. It is presumed that the victims died instantly when the Titan, roughly the size of an SUV, imploded under the immense pressure of the North Atlantic at a depth of over two miles (nearly four kilometers).

Both the US Coast Guard and Canadian authorities have launched investigations into the cause of the tragedy, which occurred after the Titan lost contact about an hour and 45 minutes into its descent.