All five people on the missing submersible are believed to have died from a catastrophic implosion; parts of the vessel have been identified on the ocean floor

Colombo (News 1st) - All five people on board the missing submersible are now known to have died instantly from a catastrophic implosion, as parts of the vessel have been identified on the ocean floor near the Titanic, the US Coast Guard announced.

A robotic operational vessel (ROV) which reached the ocean floor four days after the submersible went missing, sent back live footage of the debris field about 500 meters off the bow section of the Titanic.

Five parts from the submersible were identified, including the tail cone and landing frame, the Coast Guard said.

It is believed that the submersible had a loss of pressure and a catastrophic implosion last Sunday as it descended to the site 3,800 meters below sea level.

No bodies have been found. The pressure at that depth would be expected to instantly vaporize the bodies.

More than a dozen search vessels from three countries - the US, Canada and France - had joined the search. Some of the search vessels will now return to port, but the ROVs and their mother ships will remain to explore the debris of the submersible, said US Coast Guard spokesman Rear Admiral John Mauger.

The search over four days concentrated on the surface of the ocean in the hope that the vessel may have come to the surface.

The first ships with ROVs arrived on Thursday and two ROVs - one Canadian, one French - were sent down. The submersible's debris field was found in a spot where there were no parts of the Titanic from the 1912 sinking of the luxury cruise liner in which 1,500 died.

The US Navy had detected the sound of an underwater implosion at the time the vessel vanished on Sunday. But the sound could not be determined as definitely from the submersible. However, the implosion was likely to have occurred last Sundayas no sounds of implosions were heard during the search over four days.

Banging noises heard earlier which had led to hopes that the vessel was intact, were likely to have been sounds from other ships.

Those on board the ill-fated vessel were:

• Hamish Harding, 58, a British billionaire adventurer who has been to space and made trips the South Pole
• Pakistani-British billionaire businessman Shahzada Dawood, 48, from one of Pakistan's richest families 
• His son Suleman Dawood, a 19-year-old student
• Paul-Henry Nargeolet, 77, a former French Navy officer who had spent more time at the Titanic wreck than any other explorer and was part of the first expedition to visit it in 1987
• Stockton Rush, 61, the CEO of OceanGate, the firm that owns the lost submersible and was its pilot on this voyage