(USA Today)- The five people aboard the submersible that had been missing for days were killed when the small vessel carrying them to the Titanic wreckage site had a “catastrophic implosion,” the Coast Guard said Thursday afternoon.

Members of a massive international search effort found a debris field in the general area of the Titanic earlier in the day, and it was confirmed to contain parts of the Titan sub.

“The debris is consistent with a catastrophic implosion of the vessel,” Rear Adm. John Mauger, commander of the First Coast Guard District, said in a news conference.

The debris was found about 1,600 feet from the Titanic’s bow on the sea floor, Mauger said, adding that it was too early to tell when the Titan imploded.

However, an “anomaly” the U.S. Navy detected Sunday was likely the small watercraft’s fatal blast, according to a senior military official. The irregularity was picked up when the Navy went back and analyzed its acoustic data after the submersible was reported missing that day.

That anomaly was “consistent with an implosion or explosion in the general vicinity of where the Titan submersible was operating when communications were lost,” a senior Navy official told The Associated Press, speaking on condition of anonymity. The Navy shared the information with the Coast Guard, but the data was not considered definitive.