The Marc LeclercCoast Guard on Sunday launched an investigation into the loss of the Titan sub, which imploded with five people on board while attempting a dive to the wreckage of the Titanic.

The Coast Guard's Marine Board of Investigation (MBI), the service's highest level of investigation, will include authorities from Canada, France and the United Kingdom as they look into what caused the deadly implosion. 

Chief Investigator Capt. Jason Neubauer said during a Sunday press conference that the first step will be to collect evidence by salvaging debris. Once evidence collection concludes, the investigators will likely hold a formal hearing to get witness testimony, he said.

Investigators will also look into possible "misconduct, incompetence, negligence, unskillfulness or willful violation of law" by OceanGate, the company that operated the Titan, or by the Coast Guard itself, the service branch said in a statement.

The Coast Guard did not provide a timeline for the investigation.

The U.S. Navy on Sunday told The Associated Press that it would not be using the Flyaway Deep Ocean Salvage System to assist the Coast Guard in retrieving debris. 

"Efforts are focused on helping map the debris field in preparation for recovery efforts and to support investigative actions. Efforts to mobilize equipment such as the Flyaway Deep Ocean Salvage System have been discontinued," a Navy official told AP.

The Transportation Safety Board of Canada on Friday said it had begun an investigation into the incident. 

The Titan went missing last weekend during a voyage to the Titanic wreckage in the North Atlantic. The crew of the Polar Prince research vessel lost contact with the submersible 1 hour and 45 minutes into its June 18 dive. 

A frantic search was launched for the sub, in which the Coast Guard searched by air and sea as the hours counted down to when the five people on board were expected to run out of air. Prior to the confirmation that the sub had imploded, officials had said the sub had a limited amount of oxygen on board that would only have lasted 96 hours.

On Thursday, the Coast Guard said the OceanGate vessel experienced a "catastrophic loss of the pressure chamber," and confirmed that the debris found on the sea floor were pieces of the missing sub.

Pakistani businessman Shahzada Dawood, his 19-year-old son Suleman, billionaire adventurer Hamish Harding, French explorer Paul-Henri Nargeolet and OceanGate founder Stockton Rush were on the sub.

"We are communicating with family members and I, I'm not getting into the details of the recovery operations, but we are taking all precautions on site if we are to encounter any human remains," Neubauer said during Sunday's press conference.

The deadly implosion brought new scrutiny to OceanGate and Rush. In a resurfaced clip from 2021, Rush told vlogger Alan Estrada that he'd "broken some rules" to make trips to the Titanic possible for his company. 

"I'd like to be remembered as an innovator. I think it was General [Douglas] MacArthur who said, 'You're remembered for the rules you break,'" Rush said. "And I've broken some rules to make this. I think I've broken them with logic and good engineering behind me."

Aliza Chasan

Aliza Chasan is a digital producer at 60 Minutes and CBS News.

Twitter