(NEXSTAR) — The dayslong search for the Titan submersible and her five crew, all bound for the wreckage of the Titanic on the Atlantic Ocean’s floor, has come to a tragic end after the U.S. Coast Guard confirmed Thursday that debris from the vessel has been found.

The submersible, belonging to OceanGate, Inc., suffered a “catastrophic implosion” less than two hours after it began its underwater journey, authorities have determined. The cause of that implosion remains under investigation.

Rescuers searched frantically for the Titan, using ships, planes, and deepsea robots. Ultimately, pieces of the Titan, including its nose cone, parts of the hull, and bells, were found 1,600 feet from the bow of the Titanic.

Despite the proximity to the ship’s wreckage, it’s unlikely those aboard ever saw the Titanic, retired Navy submariner Mark Martin told Nexstar’s WFLA.

“The reason for that is, if the unconfirmed report of a sound event that happened very close to the time they lost communications means that’s when they imploded,” he explained. “At most, they were three-quarters of the way down.”

During Thursday’s press conference, Rear Admiral John W. Mauger, of the U.S. Coast Guard, couldn’t say exactly when the Titan suffered the implosion. He noted that sonar equipment used by search teams didn’t detect anything “catastrophic” since first being used at the site.

Officials have confirmed the Titan submersible lost contact with its above-water support crew roughly an hour and 45 minutes after it began its dive. The Titan was expected to take roughly two and a half hours to reach the Titanic’s wreckage.

Now, authorities say they will continue to investigate and search for more pieces of the vessel.

Michael Bartiromo contributed to this report.