The Titan sub was likely trying to surface and the passengers probably knew the hull was 'starting to crack' before it imploded, James Cameron says

insider: Filmmaker and Titanic expert James Cameron told ABC News that the Titan submersible was likely trying to resurface after losing all communications with the outside world hours into a deep-sea mission Sunday and that the five passengers on board likely knew of a problem before the vessel collapsed in a catastrophic implosion.

"This OceanGate sub had sensors on the inside of the hull to give them a warning when it was starting to crack," Cameron said on a Thursday appearance on ABC. "And I think, if that's your idea of safety, then you're doing it wrong."

"They probably had warning that their hull was starting to delaminate and starting to crack," he said.

"It's our belief, we understand from inside the community, that they had dropped their ascent weights, and they were coming up, trying to manage an emergency," Cameron added.

Cameron has been vocal in his criticisms of the Titan sub and has said that he and engineers in the deep sea community warned OceanGate of the vessel's poor build and the strong likelihood that something "catastrophic" could potentially happen on one of their missions to the Titanic shipwreck, nearly 13,000 feet down into the ocean.

The sub went missing an hour and 45 minutes into the dive to the Titanic wreck, prompting a massive search led by the US Coast Guard that began on Monday.

On Thursday, the Coast Guard announced they had found a "debris field" of pieces of the Titan and that it had imploded during its mission. The five passengers were all presumed to be dead.

Later Thursday, the Wall Street Journal reported that the US Navy heard implosion-like sounds on a top-secret sonar system Sunday, just hours after the sub lost communication with its mother ship. It took until Thursday to deploy the proper ROVs to the scene to confirm that the sound was consistent with the Titan debris.

It remains unclear whether the vessel even made it to its desired endpoint, the Titanic wreck, and when exactly in its journey that it imploded.