U.S. Coast Guard officials gave a final update Sunday on the search for the missing Titan submersible, an effort that ended in tragedy when searchers found debris from the vessel on the ocean floor near the Titanic wreck which led them to believe the five-person crew is dead following a catastrophic implosion.
"The discovery of the Titan submersible marked the end of the U.S. Coast Guard search and rescue mission," officials said.
The Coast Guard has now opened a Marine Board of Investigation -- the highest level of investigation that the Coast Guard conducts -- with the goal of preventing a similar tragedy from occurring again.
"The board will first and primarily work to find the cause of the tragedy," and to recommend civil or criminal charges that may be warranted, officials said Sunday.
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The sub lost all communication last week on its journey to the Titanic's wreckage in the North Atlantic, and the US Coast Guard says they have found a debris field that almost certainly belongs to the Titan.
Many more questions remain, though, about the ordeal, including what went wrong and what officials knew about it.
Over the coming months, investigators are expected to focus on the how and the why behind the sub's implosion, while officials look into whether or not more regulations are needed to prevent this from happening again.
For now, resources that were deployed for this search operation are being pulled back, except some underwater vehicles known as ROVs, or remote operated vehicles.
These deep-sea robots will continue to scan the bottom of the ocean, with hopes of recovering more parts of the Titan sub and any remains of the five men who died in the implosion.
The Navy says that implosion could have been detected on Sunday, right around the time that communication with the sub failed.
Crews using an ROV owned by a Cape Cod company found the debris field on Thursday linked to the submersible, about 1,600 feet away from the Titanic wreckage site. That debris included landing gear, the rear cove and the frame of the missing underwater vessel.
"We're going to continue remote operations on the sea floor and I don't have a timeline for when we intend to stop remote operations on the seaport," Rear Admiral John Mauger, Commander of the 1st Coast Guard District in Boston, said.
