The pilot and passengers of a submersible that went missing near the Titanic wreckage are believed to be dead, according to the U.S. Coast Guard and the company that operated the vessel.

The news was announced Thursday afternoon by both entities. It follows a dayslong hunt for the five-person crew, who left on a tourist expedition Sunday.

Earlier on Thursday, the Coast Guard said that a remote-operated vehicle discovered a debris field in the search area. During a press conference, Rear Adm. John Mauger said that five major pieces of debris found approximately 1,600 feet from the bow of the Titanic on the sea floor signaled to authorities that it was the remains of the submersible.

In consultation with experts in the unified command, the debris is consistent with the catastrophic loss of the pressure chamber, Mauger said. Upon this determination, we immediately notified the families.

On behalf of the U.S. Coast Guard and the entire unified command, I offer my deepest condolences to the families, he continued. I hope that this discovery provides some solace during this difficult time.

The 22-foot craft disappeared Sunday en route to the deep-sea wreckage of the Titanic, carrying a small crew with passengers who paid up to $250,000. The vessel was operated by OceanGate, a private company based in Washington state.

An international team using planes, ships, robots and buoys had frantically hunted for the submersible, contending with rough conditions and a search area roughly double the size of Connecticut . Experts said the craft likely had just 96 hours of oxygen, predicted to be exhausted sometime Thursday morning.

Underwater banging sounds were repeatedly detected, but Mauger said there appeared to be no link between the noises and the submersible.

This was a catastrophic implosion of the vessel, which would have generated a significant broadband sound that would have been recognized via sonar detection, Mauger said.

The vessel was carrying five people: The founder of OceanGate, Stockton Rush, who served as the pilot; Hamish Harding, a British businessperson and explorer who holds several Guinness World Records; Paul-Henri Nargeolet, a maritime expert who has been on nearly three dozen dives to the Titanic site; Shahzada Dawood, a British-Pakistani businessperson; and Dawoods 19-year-old son, Suleman.

These men were true explorers who shared a distinct spirit of adventure, and a deep passion for exploring and protecting the worlds oceans. Our hearts are with these five souls and every member of their families during this tragic time, a statement from OceanGate read on Thursday. We grieve the loss of life and joy they brought to everyone they knew.

The Coast Guard said that there is little chance of rescue crews being able to find the passengers remains, but that the remote-operated vehicle will remain at the debris site to gather more information about what happened to the submersible after it lost contact.