"A debris field was discovered within the search area by an ROV near the Titanic," the USCG said just before noon. ROV stands for remotely operated vehicle. Experts were evaluating the information. The Titan lost contact with its surface vessel, the Polar Prince, around 1 hour and 45 minutes into its dive Sunday morning, about 900 miles east of Cape Cod, Massachusetts, and around 400 miles southeast of St John's, in Canada's Newfoundland. "We understand debris has been found which may be the landing frame and a rear cover of the tail instrument compartment of The Titan lost on previous dives," Richard Garriott, the president of the Explorers Club which had members on the missing sub, wrote to the group, according to a spokesman. "We hear there may be additional debris, but no updated visuals of the submersible." This file image provided by OceanGate shows the Titan submersible descending into the ocean.

A former OceanGate Expeditions customer who took a trip to see the Titanic wreckage two years ago described the dive as a "kamikaze operation." An international search and rescue operation is ongoing for five crew members on OceanGate's Titan sub, which went missing Sunday on a planned deep sea tourist expedition. Arthur Loibl, a retired German businessman and adventurer who went on the same trip in 2021, shared his experience with OceanGate in an interview with The Associated Press. "You have to be a little bit crazy to do this sort of thing," Loibl said. He explained that the idea of touring the Titanic wreckage came to him on a trip to the South Pole in 2016.

Inside the sealed vehicle are OceanGate CEO Stockton Rush; British businessman turned adventurer Hamish Harding; father-and-son Shahzada and Suleman Dawood, who are members of one of Pakistan's wealthiest families; and Paul-Henry Nargeolet, a former French navy officer and leading Titanic expert. The U.S. Coast Guard headed a unified command that involved commercial assets, research vehicles and military counterparts from Canada, France and the United Kingdom.

While ROVs vary in design and capability, they can generally travel much deeper than manned vessels, Englot said. "Those kind of vehicles usually have robotic arms that are capable of carrying a payload, grasping an object, grabbing and turning a knob or a valve or something like that," he added. As of Thursday morning, several with the ability to reach the ocean floor had been deployed in the Atlantic as the Titan's estimated initial supply of 96 hours of oxygen dwindled – including the Victor 6000, which descended from the French L'Atalante research vessel to the ocean floor. File image of an asset of the rescue efforts – the Victor 6000 – an unmanned French robot which can dive up to 6,000 metres. It has arms that can be remotely controlled to cut cables or otherwise help release a stuck vessel. However, it does not have the capability of lifting the submersible on its own.