The US Coast Guard says it has discovered a debris field within the search area for the missing Titan submersible.
The debris field was discovered by a remote-controlled underwater search vehicle (ROV) near the wreck of the Titanic.
Experts are now evaluating the information to determine whether it is linked to the submersible.
A Coast Guard news conference is scheduled for Thursday afternoon.
The Titan vessel went missing in a remote area of the North Atlantic on Sunday with a four-day oxygen supply for its crew of five.
Some experts have speculated that it may have suffered a catastrophic implosion as a result of a hull failure. The minivan-sized submersible, which was owned and operated by the private company OceanGate Expeditions, is yet to be located.
It is unclear whether the debris is part of the Titan. Deep sea diving experts have warned that the seafloor near the Titanic’s wreckage is littered with debris.
If it is found, it will need to be reached by complex rescue equipment and then brought to the surface in an operation that would likely take hours.
Authorities and experts have expressed concern that oxygen levels onboard may nearly be depleted, prompting a sense of urgency as ships, ROVs and aircraft from the US, Canada and France continue the search.
The condition of the vessel and the five people onboard remains unknown, but the Coast Guard said on Wednesday that the search remains a rescue mission.
“This is a search-and-rescue mission, 100%,” Captain Jamie Frederick told reporters on Wednesday.
Earlier in the week, Canadian search planes reported hearing undersea noises. It remains unclear what these noises were, and authorities have cautioned they may not have been related to the Titan.
Thursday’s announcement that a debris field was found is so far the only potential clue discovered by ROVs that have been deployed to the area.
One of the ROVs, deployed from the Canadian vessel Horizon Arctic, reached the ocean floor early Thursday morning. Several more were expected to arrive later in the day.
A French research ship, the Atalante, also arrived in the area on Thursday morning and deployed its own ROV, the US Coast Guard said. That robot is capable of researching depths below the Titanic wreck, which lies about 12,500 ft (3,810m) below the surface, and has experience of surveying the Titanic.
The overall area of sea being scoured is about 26,000 sq km (10,000 sq miles), twice the size of the US state of Connecticut. The area is prone to stormy conditions and poor visibility which makes search operations more challenging, experts say.
On board the 21-foot vessel is British businessman Hamish Harding, British-Pakistani businessman Shahzada Dawood and his son Suleman, former French navy diver Paul-Henry Nargeolet and the CEO of OceanGate – which operates the submersible – Stockton Rush.
