https://www.vice.com/en_us/article/qjvj4b/the-titanic-submarine-suffered-catastrophic-implosion-crew-is-dead-oceangate-and-coast-guard-say

The sea exploration company OceanGate now believes that the five people aboard the Titan submersible “have sadly been lost,” the company said in a statement released Thursday. The Coast Guard added that they believe there was a "catastrophic implosion" that destroyed the submarine.

The search for the Titan, which was first reported missing on Sunday, had garnered international attention as onlookers hoped that the sub could be rescued before the passengers ran out of oxygen. On Thursday, however, the U.S. Coast Guard said it had discovered a “debris field” close to the Titanic shipwreck, which those aboard had been on their way to view.