Officials in the US have said they are “not sure” they can recover the bodies of five people who died on board the Titan submersible in a “catastrophic implosion”.

Debris were found on Thursday on the North Atlantic Ocean sea floor around 1,600ft from the bow of the Titanic – and the US Coast Guard has been questioned about whether the bodies can be recovered, if there should be changes to safety ratings or inspections and which vessels will remain at the scene.

In a press conference in Boston on Thursday, Rear Admiral John Mauger told reporters he could not say what the prospects were of recovering the bodies of those killed on the Titan expedition.

He said: “This is an incredibly unforgiving environment down there on the sea floor and the debris is consistent with a catastrophic implosion of the vessel.

“And so we’ll continue to work and continue to search the area down there, but I don’t have an answer for prospects at this time.”

And when asked what the next phase will be, Rear Admiral Mauger said they will continue to investigate the site and try to give the families some answers.

He added: “Our thoughts are with the families and making sure that they have an understanding as best as we can provide of what happened and begin to find some closure.

“In terms of the large process, we’re going to continue to investigate the site of the debris field and then I know that there’s also a lot of questions about how, why and when did this happen, and so those are questions that we will collect as much information as we can on now, while the governments are meeting and discussing what an investigation of this nature of a casualty might look like.

“This is something that happened, I’ll just remind everybody, this is something that happened in a remote portion of the ocean with people from, you know, several different countries around the world and so it is a complex case to work through but I’m confident that those questions will begin to get answered.”

Some of the vessels currently at the scene of the search will begin to be demobilised over the next 24 hours, but remote operations on the sea floor will continue, Rear Admiral Mauger added.

He also said he does not have a timeline for when the remote operations will finish.

When asked about whether there should be changes to safety ratings or inspections, Rear Admiral Mauger said it will be the focus of a future review.